[BUG]
Test case generic/475 have a very high chance (almost 100%) to hit a fs
hang, where a data page will never be unlocked and hang all later
operations.
[CAUSE]
In btrfs_do_readpage(), if we hit an error from submit_extent_page() we
will try to do the cleanup for our current io range, and exit.
This works fine for PAGE_SIZE == sectorsize cases, but not for subpage.
For subpage btrfs_do_readpage() will lock the full page first, which can
contain several different sectors and extents:
btrfs_do_readpage()
|- begin_page_read()
| |- btrfs_subpage_start_reader();
| Now the page will have PAGE_SIZE / sectorsize reader pending,
| and the page is locked.
|
|- end_page_read() for different branches
| This function will reduce subpage readers, and when readers
| reach 0, it will unlock the page.
But when submit_extent_page() failed, we only cleanup the current
io range, while the remaining io range will never be cleaned up, and the
page remains locked forever.
[FIX]
Update the error handling of submit_extent_page() to cleanup all the
remaining subpage range before exiting the loop.
Please note that, now submit_extent_page() can only fail due to
sanity check in alloc_new_bio().
Thus regular IO errors are impossible to trigger the error path.
[BUG]
There is a report that a btrfs has a bad super block num devices.
This makes btrfs to reject the fs completely.
BTRFS error (device sdd3): super_num_devices 3 mismatch with num_devices 2 found here
BTRFS error (device sdd3): failed to read chunk tree: -22
BTRFS error (device sdd3): open_ctree failed
[CAUSE]
During btrfs device removal, chunk tree and super block num devs are
updated in two different transactions:
btrfs_rm_device()
|- btrfs_rm_dev_item(device)
| |- trans = btrfs_start_transaction()
| | Now we got transaction X
| |
| |- btrfs_del_item()
| | Now device item is removed from chunk tree
| |
| |- btrfs_commit_transaction()
| Transaction X got committed, super num devs untouched,
| but device item removed from chunk tree.
| (AKA, super num devs is already incorrect)
|
|- cur_devices->num_devices--;
|- cur_devices->total_devices--;
|- btrfs_set_super_num_devices()
All those operations are not in transaction X, thus it will
only be written back to disk in next transaction.
So after the transaction X in btrfs_rm_dev_item() committed, but before
transaction X+1 (which can be minutes away), a power loss happen, then
we got the super num mismatch.
This has been fixed by commit bbac58698a55 ("btrfs: remove device item
and update super block in the same transaction").
[FIX]
Make the super_num_devices check less strict, converting it from a hard
error to a warning, and reset the value to a correct one for the current
or next transaction commit.
As the number of device items is the critical information where the
super block num_devices is only a cached value (and also useful for
cross checking), it's safe to automatically update it. Other device
related problems like missing device are handled after that and may
require other means to resolve, like degraded mount. With this fix,
potentially affected filesystems won't fail mount and require the manual
repair by btrfs check.
[BUG]
If we hit an error from submit_extent_page() inside
__extent_writepage_io(), we could still return 0 to the caller, and
even trigger the warning in btrfs_page_assert_not_dirty().
[CAUSE]
In __extent_writepage_io(), if we hit an error from
submit_extent_page(), we will just clean up the range and continue.
This is completely fine for regular PAGE_SIZE == sectorsize, as we can
only hit one sector in one page, thus after the error we're ensured to
exit and @ret will be saved.
But for subpage case, we may have other dirty subpage range in the page,
and in the next loop, we may succeeded submitting the next range.
In that case, @ret will be overwritten, and we return 0 to the caller,
while we have hit some error.
[FIX]
Introduce @has_error and @saved_ret to record the first error we hit, so
we will never forget what error we hit.
The following error message lack the "0x" obviously:
cannot mount because of unsupported optional features (4000)
Add the prefix to make it less confusing. This can happen on older
kernels that try to mount a filesystem with newer features so it makes
sense to backport to older trees.
CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current implementation of PTRACE_KILL is buggy and has been for
many years as it assumes it's target has stopped in ptrace_stop. At a
quick skim it looks like this assumption has existed since ptrace
support was added in linux v1.0.
While PTRACE_KILL has been deprecated we can not remove it as
a quick search with google code search reveals many existing
programs calling it.
When the ptracee is not stopped at ptrace_stop some fields would be
set that are ignored except in ptrace_stop. Making the userspace
visible behavior of PTRACE_KILL a noop in those case.
As the usual rules are not obeyed it is not clear what the
consequences are of calling PTRACE_KILL on a running process.
Presumably userspace does not do this as it achieves nothing.
Replace the implementation of PTRACE_KILL with a simple
send_sig_info(SIGKILL) followed by a return 0. This changes the
observable user space behavior only in that PTRACE_KILL on a process
not stopped in ptrace_stop will also kill it. As that has always
been the intent of the code this seems like a reasonable change.
Cc: stable@vger.kernel.org Reported-by: Al Viro <viro@zeniv.linux.org.uk> Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Tested-by: Kees Cook <keescook@chromium.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Link: https://lkml.kernel.org/r/20220505182645.497868-7-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
xtensa is the last user of the PT_SINGLESTEP flag. Changing tsk->ptrace in
user_enable_single_step and user_disable_single_step without locking could
potentiallly cause problems.
So use a thread info flag instead of a flag in tsk->ptrace. Use TIF_SINGLESTEP
that xtensa already had defined but unused.
Remove the definitions of PT_SINGLESTEP and PT_BLOCKSTEP as they have no more users.
User mode linux is the last user of the PT_DTRACE flag. Using the flag to indicate
single stepping is a little confusing and worse changing tsk->ptrace without locking
could potentionally cause problems.
So use a thread info flag with a better name instead of flag in tsk->ptrace.
Remove the definition PT_DTRACE as uml is the last user.
If kthread_is_per_cpu runs concurrently with free_kthread_struct the
kthread_struct that was just freed may be read from.
This bug was introduced by commit 40966e316f86 ("kthread: Ensure
struct kthread is present for all kthreads"). When kthread_struct
started to be allocated for all tasks that have PF_KTHREAD set. This
in turn required the kthread_struct to be freed in kernel_execve and
violated the assumption that kthread_struct will have the same
lifetime as the task.
Looking a bit deeper this only applies to callers of kernel_execve
which is just the init process and the user mode helper processes.
These processes really don't want to be kernel threads but are for
historical reasons. Mostly that copy_thread does not know how to take
a kernel mode function to the process with for processes without
PF_KTHREAD or PF_IO_WORKER set.
Solve this by not allocating kthread_struct for the init process and
the user mode helper processes.
This is done by adding a kthread member to struct kernel_clone_args.
Setting kthread in fork_idle and kernel_thread. Adding
user_mode_thread that works like kernel_thread except it does not set
kthread. In fork only allocating the kthread_struct if .kthread is set.
I have looked at kernel/kthread.c and since commit 40966e316f86
("kthread: Ensure struct kthread is present for all kthreads") there
have been no assumptions added that to_kthread or __to_kthread will
not return NULL.
There are a few callers of to_kthread or __to_kthread that assume a
non-NULL struct kthread pointer will be returned. These functions are
kthread_data(), kthread_parmme(), kthread_exit(), kthread(),
kthread_park(), kthread_unpark(), kthread_stop(). All of those functions
can reasonably expected to be called when it is know that a task is a
kthread so that assumption seems reasonable.
Cc: stable@vger.kernel.org Fixes: 40966e316f86 ("kthread: Ensure struct kthread is present for all kthreads") Reported-by: Максим Кутявин <maximkabox13@gmail.com> Link: https://lkml.kernel.org/r/20220506141512.516114-1-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the system runs out of enclave memory, SGX can reclaim EPC pages
by swapping to normal RAM. These backing pages are allocated via a
per-enclave shared memory area. Since SGX allows unlimited over
commit on EPC memory, the reclaimer thread can allocate a large
number of backing RAM pages in response to EPC memory pressure.
When the shared memory backing RAM allocation occurs during
the reclaimer thread context, the shared memory is charged to
the root memory control group, and the shmem usage of the enclave
is not properly accounted for, making cgroups ineffective at
limiting the amount of RAM an enclave can consume.
For example, when using a cgroup to launch a set of test
enclaves, the kernel does not properly account for 50% - 75% of
shmem page allocations on average. In the worst case, when
nearly all allocations occur during the reclaimer thread, the
kernel accounts less than a percent of the amount of shmem used
by the enclave's cgroup to the correct cgroup.
SGX stores a list of mm_structs that are associated with
an enclave. Pick one of them during reclaim and charge that
mm's memcg with the shmem allocation. The one that gets picked
is arbitrary, but this list almost always only has one mm. The
cases where there is more than one mm with different memcg's
are not worth considering.
Create a new function - sgx_encl_alloc_backing(). This function
is used whenever a new backing storage page needs to be
allocated. Previously the same function was used for page
allocation as well as retrieving a previously allocated page.
Prior to backing page allocation, if there is a mm_struct associated
with the enclave that is requesting the allocation, it is set
as the active memory control group.
[ dhansen: - fix merge conflict with ELDU fixes
- check against actual ksgxd_tsk, not ->mm ]
Cc: stable@vger.kernel.org Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Link: https://lkml.kernel.org/r/20220520174248.4918-1-kristen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In crash_prepare_elf64_headers(), a buffer is allocated via vmalloc() to
store elf headers. While it's not freed back to system correctly when
kdump kernel is reloaded or unloaded. Then memory leak is caused. Fix it
by introducing x86 specific function arch_kimage_file_post_load_cleanup(),
and freeing the buffer there.
And also remove the incorrect elf header buffer freeing code. Before
calling arch specific kexec_file loading function, the image instance has
been initialized. So 'image->elf_headers' must be NULL. It doesn't make
sense to free the elf header buffer in the place.
Three different people have reported three bugs about the memory leak on
x86_64 inside Redhat.
Link: https://lkml.kernel.org/r/20220223113225.63106-2-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
According to the latest event list, the event encoding 0x55
INST_DECODED.DECODERS and 0x56 UOPS_DECODED.DEC0 are only available on
the first 4 counters. Add them into the event constraints table.
In mce_threshold_create_device(), if threshold_create_bank() fails, the
previously allocated threshold banks array @bp will be leaked because
the call to mce_threshold_remove_device() will not free it.
This happens because mce_threshold_remove_device() fetches the pointer
through the threshold_banks per-CPU variable but bp is written there
only after the bank creation is successful, and not before, when
threshold_create_bank() fails.
Add a helper which unwinds all the bank creation work previously done
and pass into it the previously allocated threshold banks array for
freeing.
intel_hid_dsm_fn_mask is a bit mask containing one bit for each function
index. Fix the function index check in intel_hid_evaluate_method
accordingly, which was missed in commit 97ab4516205e ("platform/x86:
intel-hid: fix _DSM function index handling").
Fixes: 97ab4516205e ("platform/x86: intel-hid: fix _DSM function index handling") Cc: stable@vger.kernel.org Signed-off-by: Michael Niewöhner <linux@mniewoehner.de> Link: https://lore.kernel.org/r/66f813f5bcc724a0f6dd5adefe6a9728dbe509e3.camel@mniewoehner.de Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Set "HCD_FLAG_DEFER_RH_REGISTER" to hcd->flags in xhci_run() to defer
registering primary roothub in usb_add_hcd() if xhci has two roothubs.
This will make sure both primary roothub and secondary roothub will be
registered along with the second HCD.
This is required for cold plugged USB devices to be detected in certain
PCIe USB cards (like Inateck USB card connected to AM64 EVM or J7200 EVM).
This patch has been added and reverted earier as it triggered a race
in usb device enumeration.
That race is now fixed in 5.16-rc3, and in stable back to 5.4
commit 6cca13de26ee ("usb: hub: Fix locking issues with address0_mutex")
commit 6ae6dc22d2d1 ("usb: hub: Fix usb enumeration issue due to address0
race")
[minor rebase change, and commit message update -Mathias]
CC: stable@vger.kernel.org # 5.4+ Suggested-by: Mathias Nyman <mathias.nyman@linux.intel.com> Tested-by: Chris Chiu <chris.chiu@canonical.com> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com> Link: https://lore.kernel.org/r/20220510091630.16564-3-kishon@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
as this is the only way to make sure the region is allocated.
Fix the conditional that was wrong and only tried to make already
non-sparse files non-sparse.
Cc: stable@vger.kernel.org Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some older servers seem to require the workstation name during ntlmssp
to be at most 15 chars (RFC1001 name length), so truncate it before
sending when using insecure dialects.
Link: https://lore.kernel.org/r/e6837098-15d9-acb6-7e34-1923cf8c6fe1@winds.org Reported-by: Byron Stanoszek <gandalf@winds.org> Tested-by: Byron Stanoszek <gandalf@winds.org> Fixes: 49bd49f983b5 ("cifs: send workstation name during ntlmssp session setup") Cc: stable@vger.kernel.org Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Also return EOPNOTSUPP if path is remote but nodfs was set.
Fixes: a2809d0e1696 ("cifs: quirk for STATUS_OBJECT_NAME_INVALID returned for non-ASCII dfs refs") Cc: stable@vger.kernel.org Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Apparently we need to maintain these functions with
ntfs_get_acl_ex and ntfs_set_acl_ex.
This commit fixes xfstest generic/099 Fixes: 95dd8b2c1ed0 ("fs/ntfs3: Remove unnecessary functions") Reviewed-by: Kari Argillander <kari.argillander@gmail.com> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We must check size before trying to allocate.
Size can be set for example by "ulimit -f".
Fixes xfstest generic/228 Fixes: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation") Reviewed-by: Kari Argillander <kari.argillander@gmail.com> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If size of file was reduced, we still kept allocated blocks.
This commit makes ntfs3 work as other fs like btrfs. Link: https://bugzilla.kernel.org/show_bug.cgi?id=214719 Fixes: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation") Reported-by: Ganapathi Kamath <hgkamath@hotmail.com> Tested-by: Ganapathi Kamath <hgkamath@hotmail.com> Reviewed-by: Kari Argillander <kari.argillander@gmail.com> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Two problems:
1. ntfs3_setattr can't truncate preallocated space;
2. if allocated fragment "cross" valid size, then fragment splits into two parts:
- normal part;
- unwritten part (here we must return FIEMAP_EXTENT_LAST).
Before this commit we returned FIEMAP_EXTENT_LAST for whole fragment.
Fixes xfstest generic/092 Fixes: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation") Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Update valid size if write is still in I/O queue.
Fixes xfstest generic/240 Fixes: 82cae269cfa9 ("fs/ntfs3: Add initialization of super block") Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ntfs3 filesystem lacks the 'invalidate_folio' method and it causes
memory leak. If you write to the filesystem and then unmount it, the
cached written data are not freed and they are permanently leaked. Fixes: 7ba13abbd31e ("fs: Turn block_invalidatepage into block_invalidate_folio") Reported-by: José Luis Lara Carrascal <manualinux@yahoo.es> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: stable@vger.kernel.org # v5.18 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It has been observed with certain PCIe USB cards (like Inateck connected
to AM64 EVM or J7200 EVM) that as soon as the primary roothub is
registered, port status change is handled even before xHC is running
leading to cold plug USB devices not detected. For such cases, registering
both the root hubs along with the second HCD is required. Add support for
deferring roothub registration in usb_add_hcd(), so that both primary and
secondary roothubs are registered along with the second HCD.
This patch has been added and reverted earier as it triggered a race
in usb device enumeration.
That race is now fixed in 5.16-rc3, and in stable back to 5.4
commit 6cca13de26ee ("usb: hub: Fix locking issues with address0_mutex")
commit 6ae6dc22d2d1 ("usb: hub: Fix usb enumeration issue due to address0
race")
CC: stable@vger.kernel.org # 5.4+ Suggested-by: Mathias Nyman <mathias.nyman@linux.intel.com> Tested-by: Chris Chiu <chris.chiu@canonical.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com> Link: https://lore.kernel.org/r/20220510091630.16564-2-kishon@ti.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When dwc3_gadget_ep_cleanup_completed_requests() called to
dwc3_gadget_giveback() where the dwc3 lock is released, other thread is
able to execute. In this situation, usb_ep_disable() gets the chance to
clear endpoint descriptor pointer which leds to the null pointer
dereference problem. So needs to move the null pointer check to a proper
place.
Running the driver through kasan gives an interesting splat:
BUG: KASAN: global-out-of-bounds in isp1760_register+0x180/0x70c
Read of size 20 at addr f1db2e64 by task swapper/0/1
(...)
isp1760_register from isp1760_plat_probe+0x1d8/0x220
(...)
This happens because the loop reading the regmap fields for the
different ISP1760 variants look like this:
for (i = 0; i < HC_FIELD_MAX; i++) { ... }
Meaning it expects the arrays to be at least HC_FIELD_MAX - 1 long.
However the arrays isp1760_hc_reg_fields[], isp1763_hc_reg_fields[],
isp1763_hc_volatile_ranges[] and isp1763_dc_volatile_ranges[] are
dynamically sized during compilation.
Fix this by putting an empty assignment to the [HC_FIELD_MAX]
and [DC_FIELD_MAX] array member at the end of each array.
This will make the array one member longer than it needs to be,
but avoids the risk of overwriting whatever is inside
[HC_FIELD_MAX - 1] and is simple and intuitive to read. Also
add comments explaining what is going on.
Fixes: 1da9e1c06873 ("usb: isp1760: move to regmap for register access") Cc: stable@vger.kernel.org Cc: Rui Miguel Silva <rui.silva@linaro.org> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Reviewed-by: Rui Miguel Silva <rui.silva@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20220516091424.391209-1-linus.walleij@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The BG95 modem has 3 USB configurations that are configurable via the AT
command AT+QCFGEXT="usbnet",["ecm"|"modem"|"rmnet"] which make the modem
enumerate with the following interfaces, respectively:
At closing a USB MIDI output substream, there might be still a pending
work, which would eventually access the rawmidi runtime object that is
being released. For fixing the race, make sure to cancel the pending
work at closing.
Set microphone pins 0x18 (rear) and 0x19 (front) to VREF_50 to fix the
microphone noise on ASUS TUF B550M-PLUS which uses the ALCS1200A codec.
The initial value was VREF_80.
The same issue is also present on Windows using both the default Windows
driver and all tested Realtek drivers before version 6.0.9049.1. Comparing
Realtek driver 6.0.9049.1 (the first one without the microphone noise) to
Realtek driver 6.0.9047.1 (the last one with the microphone noise)
revealed that the fix is the result of setting pins 0x18 and 0x19 to
VREF_50.
This fix may also work for other boards that have been reported to have
the same microphone issue and use the ALC1150 and ALCS1200A codecs, since
these codecs are similar and the fix in the Realtek driver on Windows is
common for both. However, it is currently enabled only for ASUS TUF
B550M-PLUS as this is the only board that could be tested.
The 2022-model XPS 15 appears to use the same 4-speakers-on-ALC289
audio setup as the Dell XPS 15 9510, so requires the same quirk to
enable woofer output. Tested on my own 9520.
[ Move the entry to the right position in the SSID order -- tiwai ]
After commit 49b290e430d3 ("riscv: prevent compressed instructions in
alternatives"), builds with LLVM's integrated assembler fail:
In file included from arch/riscv/mm/init.c:10:
In file included from ./include/linux/mm.h:29:
In file included from ./include/linux/pgtable.h:6:
In file included from ./arch/riscv/include/asm/pgtable.h:108:
./arch/riscv/include/asm/tlbflush.h:23:2: error: expected assembly-time absolute expression
ALT_FLUSH_TLB_PAGE(__asm__ __volatile__ ("sfence.vma %0" : : "r" (addr) : "memory"));
^
./arch/riscv/include/asm/errata_list.h:33:5: note: expanded from macro 'ALT_FLUSH_TLB_PAGE'
asm(ALTERNATIVE("sfence.vma %0", "sfence.vma", SIFIVE_VENDOR_ID, \
^
./arch/riscv/include/asm/alternative-macros.h:187:2: note: expanded from macro 'ALTERNATIVE'
_ALTERNATIVE_CFG(old_content, new_content, vendor_id, errata_id, CONFIG_k)
^
./arch/riscv/include/asm/alternative-macros.h:113:2: note: expanded from macro '_ALTERNATIVE_CFG'
__ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, IS_ENABLED(CONFIG_k))
^
./arch/riscv/include/asm/alternative-macros.h:110:2: note: expanded from macro '__ALTERNATIVE_CFG'
ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c)
^
./arch/riscv/include/asm/alternative-macros.h:99:3: note: expanded from macro 'ALT_NEW_CONTENT'
".org . - (889b - 888b) + (887b - 886b)\n" \
^
<inline asm>:26:6: note: instantiated into assembly here
.org . - (889b - 888b) + (887b - 886b)
^
This error happens because LLVM's integrated assembler has a one-pass
design, which means it cannot figure out the instruction lengths when
the .org directive is outside of the subsection that contains the
instructions, which was changed by the .option directives added by the
above change.
Move the .org directives before the .previous directive so that these
directives are always within the same subsection, which resolves the
failures and does not introduce any new issues with GNU as. This was
done for arm64 in commit 966a0acce2fc ("arm64/alternatives: move length
validation inside the subsection") and commit 22315a2296f4 ("arm64:
alternatives: Move length validation in alternative_{insn, endif}").
While there is no error from the assembly versions of the macro, they
appear to have the same problem so just make the same change there as
well so that there are no problems in the future.
Move the __ARCH_WANT_MEMFD_SECRET define added in commit 7bb7f2ac24a0
("arch, mm: wire up memfd_secret system call where relevant") to
<uapi/asm/unistd.h> so __NR_memfd_secret is defined when including
<unistd.h> in userspace.
This allows the memfd_secret selftest to pass on riscv.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Link: https://lore.kernel.org/r/20220505081815.22808-1-tklauser@distanz.ch Fixes: 7bb7f2ac24a0 ("arch, mm: wire up memfd_secret system call where relevant") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
irq_work is triggered via an IPI, but the IPI infrastructure is not
included in uniprocessor kernels. As a result, irq_work never runs.
Fall back to the tick-based irq_work implementation on uniprocessor
configurations.
Fixes: 298447928bb1 ("riscv: Support irq_work via self IPIs") Signed-off-by: Samuel Holland <samuel@sholland.org> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Link: https://lore.kernel.org/r/20220430030025.58405-1-samuel@sholland.org Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Because of the stack canary feature that reads from the current task
structure the stack canary value, the thread pointer register "tp" must
be set before calling any C function from head.S: by chance, setup_vm
and all the functions that it calls does not seem to be part of the
functions where the canary check is done, but in the following commits,
some functions will.
Commit 00ab027a3b82 ("RISC-V: Add kernel image sections to the resource tree")
marked IORESOURCE_BUSY for reserved memory, which caused resource map
failed in subsequent operations of related driver, so remove the
IORESOURCE_BUSY flag. In order to prohibit userland mapping reserved
memory, mark IORESOURCE_EXCLUSIVE for it.
The code to reproduce the issue,
dts:
mem0: memory@a0000000 {
reg = <0x0 0xa0000000 0 0x1000000>;
no-map;
};
&test {
status = "okay";
memory-region = <&mem0>;
};
code:
np = of_parse_phandle(pdev->dev.of_node, "memory-region", 0);
ret = of_address_to_resource(np, 0, &r);
base = devm_ioremap_resource(&pdev->dev, &r);
// base = -EBUSY
Implement fb_is_primary_device() function, so that fbcon detects if this
framebuffer belongs to the default graphics card which was used to start
the system.
With the kernel 5.18, the system will hang on boot if it is compiled with
CONFIG_SCHED_MC. The last printed message is "Brought up 1 node, 1 CPU".
The crash happens in sd_init
tl->mask (which is cpu_coregroup_mask) returns an empty mask. This happens
because cpu_topology[0].core_sibling is empty.
Consequently, sd_span is set to an empty mask
sd_id = cpumask_first(sd_span) sets sd_id == NR_CPUS (because the mask is
empty)
sd->shared = *per_cpu_ptr(sdd->sds, sd_id); sets sd->shared to NULL
because sd_id is out of range
atomic_inc(&sd->shared->ref); crashes without printing anything
We can fix it by calling reset_cpu_topology() from init_cpu_topology() -
this will initialize the sibling masks on CPUs, so that they're not empty.
This patch also removes the variable "dualcores_found", it is useless,
because during boot, init_cpu_topology is called before
store_cpu_topology. Thus, set_sched_topology(parisc_mc_topology) is never
called. We don't need to call it at all because default_topology in
kernel/sched/topology.c contains the same items as parisc_mc_topology.
Note that we should not call store_cpu_topology() from init_per_cpu()
because it is called too early in the kernel initialization process and it
results in the message "Failure to register CPU0 device". Before this
patch, store_cpu_topology() would exit immediatelly because
cpuid_topo->core id was uninitialized and it was 0.
It places the .got.plt input section before the .got input section.
The same is true for the default linker script (ld --verbose) on most
architectures except x86/x86-64.
The binfmt_flat loader should relocate all GOT entries until it encounters
a -1 (the LONG(-1) in the linker script).
The problem is that the .got.plt input section starts with a GOTPLT header
(which has size 16 bytes on elf64-riscv and 8 bytes on elf32-riscv), where
the first word is set to -1. See the binutils implementation for riscv [1].
This causes the binfmt_flat loader to stop relocating GOT entries
prematurely and thus causes the application to crash when running.
Fix this by skipping the whole GOTPLT header, since the whole GOTPLT header
is reserved for the dynamic linker.
The GOTPLT header will only be skipped for bFLT binaries with flag
FLAT_FLAG_GOTPIC set. This flag is unconditionally set by elf2flt if the
supplied ELF binary has the symbol _GLOBAL_OFFSET_TABLE_ defined.
ELF binaries without a .got input section should thus remain unaffected.
Tested on RISC-V Canaan Kendryte K210 and RISC-V QEMU nommu_virt_defconfig.
Maris found out that the quirk for TEAC devices to work around the
clock setup is needed to apply only when the base clock is changed,
e.g. from 48000-based clocks (48000, 96000, 192000, 384000) to
44100-based clocks (44100, 88200, 176400, 352800), or vice versa,
while switching to another clock with the same base clock doesn't need
the (forcible) interface setup.
This patch implements the optimization for the TEAC clock quirk to
avoid the unnecessary interface re-setup.
Fixes: 5ce0b06ae5e6 ("ALSA: usb-audio: Workaround for clock setup on TEAC devices") Reported-by: Maris Abele <maris7abele@gmail.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220531130749.30357-1-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When passing pointer to some map value to kfunc or global func, in
verifier we are passing meta as NULL to various functions, which uses
meta->raw_mode to check whether memory is being written to. Since some
kfunc or global funcs may also write to memory pointers they receive as
arguments, we must check for write access to memory. E.g. in some case
map may be read only and this will be missed by current checks.
However meta->raw_mode allows for uninitialized memory (e.g. on stack),
since there is not enough info available through BTF, we must perform
one call for read access (raw_mode = false), and one for write access
(raw_mode = true).
Fixes: e5069b9c23b3 ("bpf: Support pointers in global func args") Fixes: d583691c47dc ("bpf: Introduce mem, size argument pair support for kfunc") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20220319080827.73251-2-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit being fixed was aiming to disallow users from incorrectly
obtaining writable pointer to memory that is only meant to be read. This
is enforced now using a MEM_RDONLY flag.
For instance, in case of global percpu variables, when the BTF type is
not struct (e.g. bpf_prog_active), the verifier marks register type as
PTR_TO_MEM | MEM_RDONLY from bpf_this_cpu_ptr or bpf_per_cpu_ptr
helpers. However, when passing such pointer to kfunc, global funcs, or
BPF helpers, in check_helper_mem_access, there is no expectation
MEM_RDONLY flag will be set, hence it is checked as pointer to writable
memory. Later, verifier sets up argument type of global func as
PTR_TO_MEM | PTR_MAYBE_NULL, so user can use a global func to get around
the limitations imposed by this flag.
This check will also cover global non-percpu variables that may be
introduced in kernel BTF in future.
Also, we update the log message for PTR_TO_BUF case to be similar to
PTR_TO_MEM case, so that the reason for error is clear to user.
It is not permitted to write to PTR_TO_MAP_KEY, but the current code in
check_helper_mem_access would allow for it, reject this case as well, as
helpers taking ARG_PTR_TO_UNINIT_MEM also take PTR_TO_MAP_KEY.
The 'n_buckets * (value_size + sizeof(struct stack_map_bucket))' part of the
allocated memory for 'smap' is never used after the memlock accounting was
removed, thus get rid of it.
[ Note, Daniel:
Commit b936ca643ade ("bpf: rework memlock-based memory accounting for maps")
moved `cost += n_buckets * (value_size + sizeof(struct stack_map_bucket))`
up and therefore before the bpf_map_area_alloc() allocation, sigh. In a later
step commit c85d69135a91 ("bpf: move memory size checks to bpf_map_charge_init()"),
and the overflow checks of `cost >= U32_MAX - PAGE_SIZE` moved into
bpf_map_charge_init(). And then 370868107bf6 ("bpf: Eliminate rlimit-based
memory accounting for stackmap maps") finally removed the bpf_map_charge_init().
Anyway, the original code did the allocation same way as /after/ this fix. ]
Fixes: b936ca643ade ("bpf: rework memlock-based memory accounting for maps") Signed-off-by: Yuntao Wang <ytcoode@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220407130423.798386-1-ytcoode@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bpf_{sk,task,inode}_storage_free() do not need to use
call_rcu_tasks_trace as no BPF program should be accessing the owner
as it's being destroyed. The only other reader at this point is
bpf_local_storage_map_free() which uses normal RCU.
Fixes: 0fe4b381a59e ("bpf: Allow bpf_local_storage to be used by sleepable programs") Signed-off-by: KP Singh <kpsingh@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20220418155158.2865678-1-kpsingh@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The data length of skb frags + frag_list may be greater than 0xffff, and
skb_header_pointer can not handle negative offset. So, here INT_MAX is used
to check the validity of offset. Add the same change to the related function
skb_store_bytes.
Fixes: 05c74e5e53f6 ("bpf: add bpf_skb_load_bytes helper") Signed-off-by: Liu Jian <liujian56@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20220416105801.88708-2-liujian56@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The combination of jit blinding and pointers to bpf subprogs causes:
[ 36.989548] BUG: unable to handle page fault for address: 0000000100000001
[ 36.990342] #PF: supervisor instruction fetch in kernel mode
[ 36.990968] #PF: error_code(0x0010) - not-present page
[ 36.994859] RIP: 0010:0x100000001
[ 36.995209] Code: Unable to access opcode bytes at RIP 0xffffffd7.
[ 37.004091] Call Trace:
[ 37.004351] <TASK>
[ 37.004576] ? bpf_loop+0x4d/0x70
[ 37.004932] ? bpf_prog_3899083f75e4c5de_F+0xe3/0x13b
The jit blinding logic didn't recognize that ld_imm64 with an address
of bpf subprogram is a special instruction and proceeded to randomize it.
By itself it wouldn't have been an issue, but jit_subprogs() logic
relies on two step process to JIT all subprogs and then JIT them
again when addresses of all subprogs are known.
Blinding process in the first JIT phase caused second JIT to miss
adjustment of special ld_imm64.
Fix this issue by ignoring special ld_imm64 instructions that don't have
user controlled constants and shouldn't be blinded.
The cnt value in the 'cnt >= BPF_MAX_TRAMP_PROGS' check does not
include BPF_TRAMP_MODIFY_RETURN bpf programs, so the number of
the attached BPF_TRAMP_MODIFY_RETURN bpf programs in a trampoline
can exceed BPF_MAX_TRAMP_PROGS.
When this happens, the assignment '*progs++ = aux->prog' in
bpf_trampoline_get_progs() will cause progs array overflow as the
progs field in the bpf_tramp_progs struct can only hold at most
BPF_MAX_TRAMP_PROGS bpf programs.
bpf_prog_pack enables sharing huge pages among multiple BPF programs.
These pages are marked as executable before the JIT engine fill it with
BPF programs. To make these pages safe, fill the hole bpf_prog_pack with
illegal instructions before making it executable.
Fixes: 57631054fae6 ("bpf: Introduce bpf_prog_pack allocator") Fixes: 33c9805860e5 ("bpf: Introduce bpf_jit_binary_pack_[alloc|finalize|free]") Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220520235758.1858153-2-song@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nfsd4_release_lockowner() holds clp->cl_lock when it calls
check_for_locks(). However, check_for_locks() calls nfsd_file_get()
/ nfsd_file_put() to access the backing inode's flc_posix list, and
nfsd_file_put() can sleep if the inode was recently removed.
Let's instead rely on the stateowner's reference count to gate
whether the release is permitted. This should be a reliable
indication of locks-in-use since file lock operations and
->lm_get_owner take appropriate references, which are released
appropriately when file locks are removed.
Reported-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We need to filter out ENOMEM in nfs_error_is_fatal_on_server(), because
running out of memory on our client is not a server error.
Reported-by: Olga Kornievskaia <aglo@umich.edu> Fixes: 2dc23afffbca ("NFS: ENOMEM should also be a fatal error.") Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The reference to `explicit_in_reply_to` is pointless as when the
reference was added in the form of "#15" [1], Section 15) was "The
canonical patch format".
The reference of "#15" had not been properly updated in a couple of
reorganizations during the plain-text SubmittingPatches era.
Fix it by using `the_canonical_patch_format`.
[1]: 2ae19acaa50a ("Documentation: Add "how to write a good patch summary" to SubmittingPatches")
Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Fixes: 5903019b2a5e ("Documentation/SubmittingPatches: convert it to ReST markup") Fixes: 9b2c76777acc ("Documentation/SubmittingPatches: enrich the Sphinx output") Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: stable@vger.kernel.org # v4.9+ Link: https://lore.kernel.org/r/64e105a5-50be-23f2-6cae-903a2ea98e18@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently it returns zero when CRQ response timed out, it should return
an error code instead.
Fixes: d8d74ea3c002 ("tpm: ibmvtpm: Wait for buffer to be set before proceeding") Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Under certain conditions uninitialized memory will be accessed.
As described by TCG Trusted Platform Module Library Specification,
rev. 1.59 (Part 3: Commands), if a TPM2_GetCapability is received,
requesting a capability, the TPM in field upgrade mode may return a
zero length list.
Check the property count in tpm2_get_tpm_pt().
Fixes: 2ab3241161b3 ("tpm: migrate tpm2_get_tpm_pt() to use struct tpm_buf") Cc: stable@vger.kernel.org Signed-off-by: Stefan Mahnke-Hartmann <stefan.mahnke-hartmann@infineon.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The imx412/imx577 sensor has a reset line that is active low not active
high. Currently the logic for this is inverted.
The right way to define the reset line is to declare it active low in the
DTS and invert the logic currently contained in the driver.
The DTS should represent the hardware does i.e. reset is active low.
So:
+ reset-gpios = <&tlmm 78 GPIO_ACTIVE_LOW>;
not:
- reset-gpios = <&tlmm 78 GPIO_ACTIVE_HIGH>;
I was a bit reticent about changing this logic since I thought it might
negatively impact @intel.com users. Googling a bit though I believe this
sensor is used on "Keem Bay" which is clearly a DTS based system and is not
upstream yet.
A PCMD (Paging Crypto MetaData) page contains the PCMD
structures of enclave pages that have been encrypted and
moved to the shmem backing store. When all enclave pages
sharing a PCMD page are loaded in the enclave, there is no
need for the PCMD page and it can be truncated from the
backing store.
A few issues appeared around the truncation of PCMD pages. The
known issues have been addressed but the PCMD handling code could
be made more robust by loudly complaining if any new issue appears
in this area.
Add a check that will complain with a warning if the PCMD page is not
actually empty after it has been truncated. There should never be data
in the PCMD page at this point since it is was just checked to be empty
and truncated with enclave mutex held and is updated with the
enclave mutex held.
Suggested-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Haitao Huang <haitao.huang@intel.com> Link: https://lkml.kernel.org/r/6495120fed43fafc1496d09dd23df922b9a32709.1652389823.git.reinette.chatre@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Haitao reported encountering a WARN triggered by the ENCLS[ELDU]
instruction faulting with a #GP.
The WARN is encountered when the reclaimer evicts a range of
pages from the enclave when the same pages are faulted back right away.
Consider two enclave pages (ENCLAVE_A and ENCLAVE_B)
sharing a PCMD page (PCMD_AB). ENCLAVE_A is in the
enclave memory and ENCLAVE_B is in the backing store. PCMD_AB contains
just one entry, that of ENCLAVE_B.
Scenario proceeds where ENCLAVE_A is being evicted from the enclave
while ENCLAVE_B is faulted in.
sgx_reclaim_pages() {
...
/*
* Reclaim ENCLAVE_A
*/
mutex_lock(&encl->lock);
/*
* Get a reference to ENCLAVE_A's
* shmem page where enclave page
* encrypted data will be stored
* as well as a reference to the
* enclave page's PCMD data page,
* PCMD_AB.
* Release mutex before writing
* any data to the shmem pages.
*/
sgx_encl_get_backing(...);
encl_page->desc |= SGX_ENCL_PAGE_BEING_RECLAIMED;
mutex_unlock(&encl->lock);
/*
* Fault ENCLAVE_B
*/
sgx_vma_fault() {
mutex_lock(&encl->lock);
/*
* Get reference to
* ENCLAVE_B's shmem page
* as well as PCMD_AB.
*/
sgx_encl_get_backing(...)
/*
* Load page back into
* enclave via ELDU.
*/
/*
* Release reference to
* ENCLAVE_B' shmem page and
* PCMD_AB.
*/
sgx_encl_put_backing(...);
/*
* PCMD_AB is found empty so
* it and ENCLAVE_B's shmem page
* are truncated.
*/
/* Truncate ENCLAVE_B backing page */
sgx_encl_truncate_backing_page();
/* Truncate PCMD_AB */
sgx_encl_truncate_backing_page();
mutex_unlock(&encl->lock);
...
}
mutex_lock(&encl->lock);
encl_page->desc &=
~SGX_ENCL_PAGE_BEING_RECLAIMED;
/*
* Write encrypted contents of
* ENCLAVE_A to ENCLAVE_A shmem
* page and its PCMD data to
* PCMD_AB.
*/
sgx_encl_put_backing(...)
/*
* Reference to PCMD_AB is
* dropped and it is truncated.
* ENCLAVE_A's PCMD data is lost.
*/
mutex_unlock(&encl->lock);
}
What happens next depends on whether it is ENCLAVE_A being faulted
in or ENCLAVE_B being evicted - but both end up with ENCLS[ELDU] faulting
with a #GP.
If ENCLAVE_A is faulted then at the time sgx_encl_get_backing() is called
a new PCMD page is allocated and providing the empty PCMD data for
ENCLAVE_A would cause ENCLS[ELDU] to #GP
If ENCLAVE_B is evicted first then a new PCMD_AB would be allocated by the
reclaimer but later when ENCLAVE_A is faulted the ENCLS[ELDU] instruction
would #GP during its checks of the PCMD value and the WARN would be
encountered.
Noting that the reclaimer sets SGX_ENCL_PAGE_BEING_RECLAIMED at the time
it obtains a reference to the backing store pages of an enclave page it
is in the process of reclaiming, fix the race by only truncating the PCMD
page after ensuring that no page sharing the PCMD page is in the process
of being reclaimed.
Cc: stable@vger.kernel.org Fixes: 08999b2489b4 ("x86/sgx: Free backing memory after faulting the enclave page") Reported-by: Haitao Huang <haitao.huang@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Haitao Huang <haitao.huang@intel.com> Link: https://lkml.kernel.org/r/ed20a5db516aa813873268e125680041ae11dfcf.1652389823.git.reinette.chatre@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Haitao reported encountering a WARN triggered by the ENCLS[ELDU]
instruction faulting with a #GP.
The WARN is encountered when the reclaimer evicts a range of
pages from the enclave when the same pages are faulted back
right away.
The SGX backing storage is accessed on two paths: when there
are insufficient free pages in the EPC the reclaimer works
to move enclave pages to the backing storage and as enclaves
access pages that have been moved to the backing storage
they are retrieved from there as part of page fault handling.
An oversubscribed SGX system will often run the reclaimer and
page fault handler concurrently and needs to ensure that the
backing store is accessed safely between the reclaimer and
the page fault handler. This is not the case because the
reclaimer accesses the backing store without the enclave mutex
while the page fault handler accesses the backing store with
the enclave mutex.
Consider the scenario where a page is faulted while a page sharing
a PCMD page with the faulted page is being reclaimed. The
consequence is a race between the reclaimer and page fault
handler, the reclaimer attempting to access a PCMD at the
same time it is truncated by the page fault handler. This
could result in lost PCMD data. Data may still be
lost if the reclaimer wins the race, this is addressed in
the following patch.
The reclaimer accesses pages from the backing storage without
holding the enclave mutex and runs the risk of concurrently
accessing the backing storage with the page fault handler that
does access the backing storage with the enclave mutex held.
In the scenario below a PCMD page is truncated from the backing
store after all its pages have been loaded in to the enclave
at the same time the PCMD page is loaded from the backing store
when one of its pages are reclaimed:
sgx_reclaim_pages() { sgx_vma_fault() {
...
mutex_lock(&encl->lock);
...
__sgx_encl_eldu() {
...
if (pcmd_page_empty) {
/*
* EPC page being reclaimed /*
* shares a PCMD page with an * PCMD page truncated
* enclave page that is being * while requested from
* faulted in. * reclaimer.
*/ */
sgx_encl_get_backing() <----------> sgx_encl_truncate_backing_page()
}
mutex_unlock(&encl->lock);
} }
In this scenario there is a race between the reclaimer and the page fault
handler when the reclaimer attempts to get access to the same PCMD page
that is being truncated. This could result in the reclaimer writing to
the PCMD page that is then truncated, causing the PCMD data to be lost,
or in a new PCMD page being allocated. The lost PCMD data may still occur
after protecting the backing store access with the mutex - this is fixed
in the next patch. By ensuring the backing store is accessed with the mutex
held the enclave page state can be made accurate with the
SGX_ENCL_PAGE_BEING_RECLAIMED flag accurately reflecting that a page
is in the process of being reclaimed.
Consistently protect the reclaimer's backing store access with the
enclave's mutex to ensure that it can safely run concurrently with the
page fault handler.
Cc: stable@vger.kernel.org Fixes: 1728ab54b4be ("x86/sgx: Add a page reclaimer") Reported-by: Haitao Huang <haitao.huang@intel.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Haitao Huang <haitao.huang@intel.com> Link: https://lkml.kernel.org/r/fa2e04c561a8555bfe1f4e7adc37d60efc77387b.1652389823.git.reinette.chatre@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Recent commit 08999b2489b4 ("x86/sgx: Free backing memory
after faulting the enclave page") expanded __sgx_encl_eldu()
to clear an enclave page's PCMD (Paging Crypto MetaData)
from the PCMD page in the backing store after the enclave
page is restored to the enclave.
Since the PCMD page in the backing store is modified the page
should be marked as dirty to ensure the modified data is retained.
Cc: stable@vger.kernel.org Fixes: 08999b2489b4 ("x86/sgx: Free backing memory after faulting the enclave page") Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Haitao Huang <haitao.huang@intel.com> Link: https://lkml.kernel.org/r/00cd2ac480db01058d112e347b32599c1a806bc4.1652389823.git.reinette.chatre@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SGX uses shmem backing storage to store encrypted enclave pages
and their crypto metadata when enclave pages are moved out of
enclave memory. Two shmem backing storage pages are associated with
each enclave page - one backing page to contain the encrypted
enclave page data and one backing page (shared by a few
enclave pages) to contain the crypto metadata used by the
processor to verify the enclave page when it is loaded back into
the enclave.
sgx_encl_put_backing() is used to release references to the
backing storage and, optionally, mark both backing store pages
as dirty.
Managing references and dirty status together in this way results
in both backing store pages marked as dirty, even if only one of
the backing store pages are changed.
Additionally, waiting until the page reference is dropped to set
the page dirty risks a race with the page fault handler that
may load outdated data into the enclave when a page is faulted
right after it is reclaimed.
Consider what happens if the reclaimer writes a page to the backing
store and the page is immediately faulted back, before the reclaimer
is able to set the dirty bit of the page:
sgx_reclaim_pages() { sgx_vma_fault() {
...
sgx_encl_get_backing();
... ...
sgx_reclaimer_write() {
mutex_lock(&encl->lock);
/* Write data to backing store */
mutex_unlock(&encl->lock);
}
mutex_lock(&encl->lock);
__sgx_encl_eldu() {
...
/*
* Enclave backing store
* page not released
* nor marked dirty -
* contents may not be
* up to date.
*/
sgx_encl_get_backing();
...
/*
* Enclave data restored
* from backing store
* and PCMD pages that
* are not up to date.
* ENCLS[ELDU] faults
* because of MAC or PCMD
* checking failure.
*/
sgx_encl_put_backing();
}
...
/* set page dirty */
sgx_encl_put_backing();
...
mutex_unlock(&encl->lock);
} }
Remove the option to sgx_encl_put_backing() to set the backing
pages as dirty and set the needed pages as dirty right after
receiving important data while enclave mutex is held. This ensures that
the page fault handler can get up to date data from a page and prepares
the code for a following change where only one of the backing pages
need to be marked as dirty.
When the NTFS BOOT sectors_per_clusters field is > 0x80, it represents a
shift value. Make sure that the shift value is not too large before using
it (NTFS max cluster size is 2MB). Return -EVINVAL if it too large.
This prevents negative shift values and shift values that are larger than
the field size.
Prevents this UBSAN error:
UBSAN: shift-out-of-bounds in ../fs/ntfs3/super.c:673:16
shift exponent -192 is negative
Link: https://lkml.kernel.org/r/20220502175342.20296-1-rdunlap@infradead.org Fixes: 82cae269cfa9 ("fs/ntfs3: Add initialization of super block") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: syzbot+1631f09646bc214d2e76@syzkaller.appspotmail.com Reviewed-by: Namjae Jeon <linkinjeon@kernel.org> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Kari Argillander <kari.argillander@stargateuniverse.net> Cc: Namjae Jeon <linkinjeon@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Raid456 module had allowed to achieve failed state. It was fixed by fb73b357fb9 ("raid5: block failing device if raid will be failed").
This fix introduces a bug, now if raid5 fails during IO, it may result
with a hung task without completion. Faulty flag on the device is
necessary to process all requests and is checked many times, mainly in
analyze_stripe().
Allow to set faulty on drive again and set MD_BROKEN if raid is failed.
As a result, this level is allowed to achieve failed state again, but
communication with userspace (via -EBUSY status) will be preserved.
This restores possibility to fail array via #mdadm --set-faulty command
and will be fixed by additional verification on mdadm side.
Cc: stable@vger.kernel.org Fixes: fb73b357fb9 ("raid5: block failing device if raid will be failed") Reviewd-by: Xiao Ni <xni@redhat.com> Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The device-mapper framework provides a mechanism to mark targets as
immutable (and hence fail table reloads that try to change the target
type). Add the DM_TARGET_IMMUTABLE flag to the dm-verity target's
feature flags to prevent switching the verity target with a different
target type.
dm-stats can be used with a very large number of entries (it is only
limited by 1/4 of total system memory), so add rescheduling points to
the loops that iterate over the entries.
The device mapper dm-crypt target is using scnprintf("%02x", cc->key[i]) to
report the current key to userspace. However, this is not a constant-time
operation and it may leak information about the key via timing, via cache
access patterns or via the branch predictor.
Change dm-crypt's key printing to use "%c" instead of "%02x". Also
introduce hex2asc() that carefully avoids any branching or memory
accesses when converting a number in the range 0 ... 15 to an ascii
character.
Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Tested-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "r" variable shadows an earlier "r" that has function scope. It
means that we accidentally return success instead of an error code.
Smatch has a warning for this:
While looking at a crash report on a timer list being corrupted, which
usually happens when a timer is freed while still active. This is
commonly triggered by code calling del_timer() instead of
del_timer_sync() just before freeing.
One possible culprit is the hci_qca driver, which does exactly that.
Eric mentioned that wake_retrans_timer could be rearmed via the work
queue, so also move the destruction of the work queue before
del_timer_sync().
Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: stable@vger.kernel.org Fixes: 0ff252c1976da ("Bluetooth: hciuart: Add support QCA chipset for UART") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The quirk entry for Focusrite Saffire 6 had no proper ep_idx for the
capture endpoint, and this confused the driver, resulting in the
broken sound. This patch adds the missing ep_idx in the entry.
While we are at it, a couple of other entries (for Digidesign MBox and
MOTU MicroBook II) seem to have the same problem, and those are
covered as well.
Maris reported that TEAC UD-501 (0644:8043) doesn't work with the
typical "clock source 41 is not valid, cannot use" errors on the
recent kernels. The currently known workaround so far is to restore
(partially) what we've done unconditionally at the clock setup;
namely, re-setup the USB interface immediately after the clock is
changed. This patch re-introduces the behavior conditionally for TEAC
devices.
Further notes:
- The USB interface shall be set later in
snd_usb_endpoint_configure(), but this seems to be too late.
- Even calling usb_set_interface() right after
sne_usb_init_sample_rate() doesn't help; so this must be related
with the clock validation, too.
- The device may still spew the "clock source 41 is not valid" error
at the first clock setup. This seems happening at the very first
try of clock setup, but it disappears at later attempts.
The error is likely harmless because the driver retries the clock
setup (such an error is more or less expected on some devices).
The asynchronous zspage free worker tries to lock a zspage's entire page
list without defending against page migration. Since pages which haven't
yet been locked can concurrently migrate off the zspage page list while
lock_zspage() churns away, lock_zspage() can suffer from a few different
lethal races.
It can lock a page which no longer belongs to the zspage and unsafely
dereference page_private(), it can unsafely dereference a torn pointer to
the next page (since there's a data race), and it can observe a spurious
NULL pointer to the next page and thus not lock all of the zspage's pages
(since a single page migration will reconstruct the entire page list, and
create_page_chain() unconditionally zeroes out each list pointer in the
process).
Fix the races by using migrate_read_lock() in lock_zspage() to synchronize
with page migration.
Link: https://lkml.kernel.org/r/20220509024703.243847-1-sultan@kerneltoast.com Fixes: 77ff465799c602 ("zsmalloc: zs_page_migrate: skip unnecessary loops but not return -EBUSY if zspage is not inuse") Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change the VF2PF interrupt handler in the PF ISR and the definition of
the internal PFVF API to correct the current implementation, which can
result in missed interrupts.
More specifically, current HW generations consider a write to the mask
register, regardless of the value, as an acknowledge of any pending
VF2PF interrupt. Therefore, if there is an interrupt between the source
register read and the mask register write, such interrupt will not be
delivered and silently acknowledged, resulting in a lost VF2PF message.
To work around the problem, rather than disabling specific interrupts,
disable all the interrupts and re-enable only the ones that we are not
serving (excluding the already disabled ones too). This will force any
other pending interrupt to be triggered and be serviced by a subsequent
ISR.
This new approach requires, however, changes to the interrupt related
pfvf_ops functions. In particular, get_vf2pf_sources() has now been
removed in favor of disable_pending_vf2pf_interrupts(), which not only
retrieves and returns the pending (and enabled) sources, but also
disables them.
As a consequence, introduce the adf_disable_pending_vf2pf_interrupts()
utility in place of adf_disable_vf2pf_interrupts_irq(), which is no
longer needed.
Cc: stable@vger.kernel.org Fixes: 993161d ("crypto: qat - fix handling of VF to PF interrupts") Signed-off-by: Marco Chiappero <marco.chiappero@intel.com> Co-developed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com> Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 358ba762d9f1 ("crypto: caam - enable prediction resistance
in HRWNG") the following CAAM errors can be seen on i.MX6SX:
caam_jr 2101000.jr: 20003c5b: CCB: desc idx 60: RNG: Hardware error
hwrng: no data available
This error is due to an incorrect entropy delay for i.MX6SX.
Fix it by increasing the minimum entropy delay for i.MX6SX
as done in U-Boot:
https://patchwork.ozlabs.org/project/uboot/patch/20220415111049.2565744-1-gaurav.jain@nxp.com/
As explained in the U-Boot patch:
"RNG self tests are run to determine the correct entropy delay.
Such tests are executed with different voltages and temperatures to identify
the worst case value for the entropy delay. For i.MX6SX, it was determined
that after adding a margin value of 1000 the minimum entropy delay should be
at least 12000."
For some sev ioctl interfaces, the length parameter that is passed maybe
less than or equal to SEV_FW_BLOB_MAX_SIZE, but larger than the data
that PSP firmware returns. In this case, kmalloc will allocate memory
that is the size of the input rather than the size of the data.
Since PSP firmware doesn't fully overwrite the allocated buffer, these
sev ioctl interface may return uninitialized kernel slab memory.
Reported-by: Andy Nguyen <theflow@google.com> Suggested-by: David Rientjes <rientjes@google.com> Suggested-by: Peter Gonda <pgonda@google.com> Cc: kvm@vger.kernel.org Cc: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org Fixes: eaf78265a4ab3 ("KVM: SVM: Move SEV code to separate file") Fixes: 2c07ded06427d ("KVM: SVM: add support for SEV attestation command") Fixes: 4cfdd47d6d95a ("KVM: SVM: Add KVM_SEV SEND_START command") Fixes: d3d1af85e2c75 ("KVM: SVM: Add KVM_SEND_UPDATE_DATA command") Fixes: eba04b20e4861 ("KVM: x86: Account a variety of miscellaneous allocations") Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Reviewed-by: Peter Gonda <pgonda@google.com>
Message-Id: <20220516154310.3685678-1-Ashish.Kalra@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Before Commit c3e5e415bc1e6 ("KVM: X86: Change kvm_sync_page()
to return true when remote flush is needed"), the return value
of kvm_sync_page() indicates whether the page is synced, and
kvm_mmu_get_page() would rebuild page when the sync fails.
But now, kvm_sync_page() returns false when the page is
synced and no tlb flushing is required, which leads to
rebuild page in kvm_mmu_get_page(). So return the return
value of mmu->sync_page() directly and check it in
kvm_mmu_get_page(). If the sync fails, the page will be
zapped and the invalid_list is not empty, so set flush as
true is accepted in mmu_sync_children().
Cc: stable@vger.kernel.org Fixes: c3e5e415bc1e6 ("KVM: X86: Change kvm_sync_page() to return true when remote flush is needed") Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com> Acked-by: Lai Jiangshan <jiangshanlai@gmail.com>
Message-Id: <0dabeeb789f57b0d793f85d073893063e692032d.1647336064.git.houwenlong.hwl@antgroup.com>
[mmu_sync_children should not flush if the page is zapped. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove WARNs that sanity check that KVM never lets a triple fault for L2
escape and incorrectly end up in L1. In normal operation, the sanity
check is perfectly valid, but it incorrectly assumes that it's impossible
for userspace to induce KVM_REQ_TRIPLE_FAULT without bouncing through
KVM_RUN (which guarantees kvm_check_nested_state() will see and handle
the triple fault).
The WARN can currently be triggered if userspace injects a machine check
while L2 is active and CR4.MCE=0. And a future fix to allow save/restore
of KVM_REQ_TRIPLE_FAULT, e.g. so that a synthesized triple fault isn't
lost on migration, will make it trivially easy for userspace to trigger
the WARN.
Clearing KVM_REQ_TRIPLE_FAULT when forcibly leaving guest mode is
tempting, but wrong, especially if/when the request is saved/restored,
e.g. if userspace restores events (including a triple fault) and then
restores nested state (which may forcibly leave guest mode). Ignoring
the fact that KVM doesn't currently provide the necessary APIs, it's
userspace's responsibility to manage pending events during save/restore.
When kernel handles the vm-exit caused by external interrupts and NMI,
it always sets kvm_intr_type to tell if it's dealing an IRQ or NMI. For
the PMI scenario, it could be IRQ or NMI.
However, intel_pt PMIs are only generated for HARDWARE perf events, and
HARDWARE events are always configured to generate NMIs. Use
kvm_handling_nmi_from_guest() to precisely identify if the intel_pt PMI
came from the guest; this avoids false positives if an intel_pt PMI/NMI
arrives while the host is handling an unrelated IRQ VM-Exit.
Fixes: db215756ae59 ("KVM: x86: More precisely identify NMI from guest when handling PMI") Signed-off-by: Yanfei Xu <yanfei.xu@intel.com>
Message-Id: <20220523140821.1345605-1-yanfei.xu@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Whenever x86_decode_emulated_instruction() detects a breakpoint, it
returns the value that kvm_vcpu_check_breakpoint() writes into its
pass-by-reference second argument. Unfortunately this is completely
bogus because the expected outcome of x86_decode_emulated_instruction
is an EMULATION_* value.
Then, if kvm_vcpu_check_breakpoint() does "*r = 0" (corresponding to
a KVM_EXIT_DEBUG userspace exit), it is misunderstood as EMULATION_OK
and x86_emulate_instruction() is called without having decoded the
instruction. This causes various havoc from running with a stale
emulation context.
The fix is to move the call to kvm_vcpu_check_breakpoint() where it was
before commit 4aa2691dcbd3 ("KVM: x86: Factor out x86 instruction
emulation with decoding") introduced x86_decode_emulated_instruction().
The other caller of the function does not need breakpoint checks,
because it is invoked as part of a vmexit and the processor has already
checked those before executing the instruction that #GP'd.
This fixes CVE-2022-1852.
Reported-by: Qiuhao Li <qiuhao@sysec.org> Reported-by: Gaoning Pan <pgn@zju.edu.cn> Reported-by: Yongkang Jia <kangel@zju.edu.cn> Fixes: 4aa2691dcbd3 ("KVM: x86: Factor out x86 instruction emulation with decoding") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220311032801.3467418-2-seanjc@google.com>
[Rewrote commit message according to Qiuhao's report, since a patch
already existed to fix the bug. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This shows up as a TDP MMU leak when running nested. Non-working cmpxchg on L0
relies makes L1 install two different shadow pages under same spte, and one of
them is leaked.
Fixes: 1c2361f667f36 ("KVM: x86: Use __try_cmpxchg_user() to emulate atomic accesses") Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220512101420.306759-1-mlevitsk@redhat.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the recently introduce __try_cmpxchg_user() to emulate atomic guest
accesses via the associated userspace address instead of mapping the
backing pfn into kernel address space. Using kvm_vcpu_map() is unsafe as
it does not coordinate with KVM's mmu_notifier to ensure the hva=>pfn
translation isn't changed/unmapped in the memremap() path, i.e. when
there's no struct page and thus no elevated refcount.
Fixes: 42e35f8072c3 ("KVM/X86: Use kvm_vcpu_map in emulator_cmpxchg_emulated") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220202004945.2540433-5-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the recently introduced __try_cmpxchg_user() to update guest PTE A/D
bits instead of mapping the PTE into kernel address space. The VM_PFNMAP
path is broken as it assumes that vm_pgoff is the base pfn of the mapped
VMA range, which is conceptually wrong as vm_pgoff is the offset relative
to the file and has nothing to do with the pfn. The horrific hack worked
for the original use case (backing guest memory with /dev/mem), but leads
to accessing "random" pfns for pretty much any other VM_PFNMAP case.
Fixes: bd53cb35a3e9 ("X86/KVM: Handle PFNs outside of kernel reach when touching GPTEs") Debugged-by: Tadeusz Struk <tadeusz.struk@linaro.org> Tested-by: Tadeusz Struk <tadeusz.struk@linaro.org> Reported-by: syzbot+6cde2282daa792c49ab8@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220202004945.2540433-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add support for CMPXCHG loops on userspace addresses. Provide both an
"unsafe" version for tight loops that do their own uaccess begin/end, as
well as a "safe" version for use cases where the CMPXCHG is not buried in
a loop, e.g. KVM will resume the guest instead of looping when emulation
of a guest atomic accesses fails the CMPXCHG.
Provide 8-byte versions for 32-bit kernels so that KVM can do CMPXCHG on
guest PAE PTEs, which are accessed via userspace addresses.
Guard the asm_volatile_goto() variation with CC_HAS_ASM_GOTO_TIED_OUTPUT,
the "+m" constraint fails on some compilers that otherwise support
CC_HAS_ASM_GOTO_OUTPUT.
Cc: stable@vger.kernel.org Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220202004945.2540433-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit ddd7ed842627 ("x86/kvm: Alloc dummy async #PF token outside of
raw spinlock") leads to the following Smatch static checker warning:
arch/x86/kernel/kvm.c:212 kvm_async_pf_task_wake()
warn: sleeping in atomic context
arch/x86/kernel/kvm.c
202 raw_spin_lock(&b->lock);
203 n = _find_apf_task(b, token);
204 if (!n) {
205 /*
206 * Async #PF not yet handled, add a dummy entry for the token.
207 * Allocating the token must be down outside of the raw lock
208 * as the allocator is preemptible on PREEMPT_RT kernels.
209 */
210 if (!dummy) {
211 raw_spin_unlock(&b->lock);
--> 212 dummy = kzalloc(sizeof(*dummy), GFP_KERNEL);
^^^^^^^^^^
Smatch thinks the caller has preempt disabled. The `smdb.py preempt
kvm_async_pf_task_wake` output call tree is:
The DEFINE_IDTENTRY_SYSVEC() is a wrapper that calls this function
from the call_on_irqstack_cond(). It's inside the call_on_irqstack_cond()
where preempt is disabled (unless it's already disabled). The
irq_enter/exit_rcu() functions disable/enable preempt.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drop the raw spinlock in kvm_async_pf_task_wake() before allocating the
the dummy async #PF token, the allocator is preemptible on PREEMPT_RT
kernels and must not be called from truly atomic contexts.
Opportunistically document why it's ok to loop on allocation failure,
i.e. why the function won't get stuck in an infinite loop.
Reported-by: Yajun Deng <yajun.deng@linux.dev> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
projects / thirdparty / kernel / stable.git / log
