Fix incorrect value mask for register write. Register values are 8-bit,
not 9. If this function was called with a value > 0xFF and an even addr,
it would cause writing to the next register.
Fixes: f2a22e1e172f ("iio: adc: ad7606: Add support for software mode for ad7616") Signed-off-by: David Lechner <dlechner@baylibre.com> Reviewed-by: Angelo Dureghello <adureghello@baylibre.com> Link: https://patch.msgid.link/20250428-iio-adc-ad7606_spi-fix-write-value-mask-v1-1-a2d5e85a809f@baylibre.com Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>From the documentation:
"offset to be added to <type>[Y]_raw prior toscaling by <type>[Y]_scale"
Offset should be applied before multiplying scale, so divide offset by
scale to make this correct.
Fixes: bc3eb0207fb5 ("iio: imu: inv_icm42600: add temperature sensor support") Signed-off-by: Sean Nyekjaer <sean@geanix.com> Acked-by: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com> Link: https://patch.msgid.link/20250502-imu-v1-1-129b8391a4e3@geanix.com Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit a4e772898f8b ("PCI: Add missing bridge lock to pci_bus_lock()")
made the lock function to call depend on dev->subordinate but left
pci_slot_unlock() unmodified creating locking asymmetry compared with
pci_slot_lock().
Because of the asymmetric lock handling, the same bridge device is unlocked
twice. First pci_bus_unlock() unlocks bus->self and then pci_slot_unlock()
will unconditionally unlock the same bridge device.
Move pci_dev_unlock() inside an else branch to match the logic in
pci_slot_lock().
Loongson PCIe Root Ports don't advertise an ACS capability, but they do not
allow peer-to-peer transactions between Root Ports. Add an ACS quirk so
each Root Port can be in a separate IOMMU group.
Interrupt and monitor pages should be in Hyper-V page size (4k bytes).
This can be different from the system page size.
This size is read and used by the user-mode program to determine the
mapped data region. An example of such user-mode program is the VMBus
driver in DPDK.
Cc: stable@vger.kernel.org Fixes: 95096f2fbd10 ("uio-hv-generic: new userspace i/o driver for VMBus") Signed-off-by: Long Li <longli@microsoft.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Link: https://lore.kernel.org/r/1746492997-4599-3-git-send-email-longli@linuxonhyperv.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <1746492997-4599-3-git-send-email-longli@linuxonhyperv.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function max14577_reg_get_current_limit() calls the function
max14577_read_reg(), but does not check its return value. A proper
implementation can be found in max14577_get_online().
Add a error check for the max14577_read_reg() and return error code
if the function fails.
Fixes: b0902bbeb768 ("regulator: max14577: Add regulator driver for Maxim 14577") Cc: stable@vger.kernel.org # v3.14 Signed-off-by: Wentao Liang <vulab@iscas.ac.cn> Link: https://patch.msgid.link/20250526025627.407-1-vulab@iscas.ac.cn Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
GCC 15 changed the default C standard dialect from gnu17 to gnu23,
which should not have impacted the kernel because it explicitly requests
the gnu11 standard in the main Makefile. However, mips/vdso code uses
its own CFLAGS without a '-std=' value, which break with this dialect
change because of the kernel's own definitions of bool, false, and true
conflicting with the C23 reserved keywords.
include/linux/stddef.h:11:9: error: cannot use keyword 'false' as enumeration constant
11 | false = 0,
| ^~~~~
include/linux/stddef.h:11:9: note: 'false' is a keyword with '-std=c23' onwards
include/linux/types.h:35:33: error: 'bool' cannot be defined via 'typedef'
35 | typedef _Bool bool;
| ^~~~
include/linux/types.h:35:33: note: 'bool' is a keyword with '-std=c23' onwards
Add -std as specified in KBUILD_CFLAGS to the decompressor and purgatory
CFLAGS to eliminate these errors and make the C standard version of these
areas match the rest of the kernel.
In mii_nway_restart() the code attempts to call
mii->mdio_read which is ch9200_mdio_read(). ch9200_mdio_read()
utilises a local buffer called "buff", which is initialised
with control_read(). However "buff" is conditionally
initialised inside control_read():
if (err == size) {
memcpy(data, buf, size);
}
If the condition of "err == size" is not met, then
"buff" remains uninitialised. Once this happens the
uninitialised "buff" is accessed and returned during
ch9200_mdio_read():
return (buff[0] | buff[1] << 8);
The problem stems from the fact that ch9200_mdio_read()
ignores the return value of control_read(), leading to
uinit-access of "buff".
To fix this we should check the return value of
control_read() and return early on error.
The above issue may happen as follows:
(1) Add kprobe tracepoint;
(2) insmod test.ko;
(3) Module triggers ftrace disabled;
(4) rmmod test.ko;
(5) cat /proc/kallsyms; --> Will trigger UAF as test.ko already removed;
ftrace_mod_get_kallsym()
...
strscpy(module_name, mod_map->mod->name, MODULE_NAME_LEN);
...
The problem is when a module triggers an issue with ftrace and
sets ftrace_disable. The ftrace_disable is set when an anomaly is
discovered and to prevent any more damage, ftrace stops all text
modification. The issue that happened was that the ftrace_disable stops
more than just the text modification.
When a module is loaded, its init functions can also be traced. Because
kallsyms deletes the init functions after a module has loaded, ftrace
saves them when the module is loaded and function tracing is enabled. This
allows the output of the function trace to show the init function names
instead of just their raw memory addresses.
When a module is removed, ftrace_release_mod() is called, and if
ftrace_disable is set, it just returns without doing anything more. The
problem here is that it leaves the mod_list still around and if kallsyms
is called, it will call into this code and access the module memory that
has already been freed as it will return:
There's a tiny race condition in dm-mirror. The functions queue_bio and
write_callback grab a spinlock, add a bio to the list, drop the spinlock
and wake up the mirrord thread that processes bios in the list.
It may be possible that the mirrord thread processes the bio just after
spin_unlock_irqrestore is called, before wakeup_mirrord. This spurious
wake-up is normally harmless, however if the device mapper device is
unloaded just after the bio was processed, it may be possible that
wakeup_mirrord(ms) uses invalid "ms" pointer.
Fix this bug by moving wakeup_mirrord inside the spinlock.
In sunxi_nfc_hw_ecc_read_chunk(), the sunxi_nfc_randomizer_enable() is
called without the config of randomizer. A proper implementation can be
found in sunxi_nfc_hw_ecc_read_chunks_dma().
Add sunxi_nfc_randomizer_config() before the start of randomization.
The function sunxi_nfc_hw_ecc_write_chunk() calls the
sunxi_nfc_hw_ecc_write_chunk(), but does not call the configuration
function sunxi_nfc_randomizer_config(). Consequently, the randomization
might not conduct correctly, which will affect the lifespan of NAND flash.
A proper implementation can be found in sunxi_nfc_hw_ecc_write_page_dma().
Add the sunxi_nfc_randomizer_config() to config randomizer.
In dirty_ratio_handler(), vm_dirty_bytes must be set to zero before
calling writeback_set_ratelimit(), as global_dirty_limits() always
prioritizes the value of vm_dirty_bytes.
It's domain_dirty_limits() that's relevant here, not node_dirty_ok:
This causes ratelimit_pages to still use the value calculated based on
vm_dirty_bytes, which is wrong now.
The impact visible to userspace is difficult to capture directly because
there is no procfs/sysfs interface exported to user space. However, it
will have a real impact on the balance of dirty pages.
For example:
1. On default, we have vm_dirty_ratio=40, vm_dirty_bytes=0
2. echo 8192 > dirty_bytes, then vm_dirty_bytes=8192,
vm_dirty_ratio=0, and ratelimit_pages is calculated based on
vm_dirty_bytes now.
3. echo 20 > dirty_ratio, then since vm_dirty_bytes is not reset to
zero when writeback_set_ratelimit() -> global_dirty_limits() ->
domain_dirty_limits() is called, reallimit_pages is still calculated
based on vm_dirty_bytes instead of vm_dirty_ratio. This does not
conform to the actual intent of the user.
Link: https://lkml.kernel.org/r/20250415090232.7544-1-alexjlzheng@tencent.com Fixes: 9d823e8f6b1b ("writeback: per task dirty rate limit") Signed-off-by: Jinliang Zheng <alexjlzheng@tencent.com> Reviewed-by: MengEn Sun <mengensun@tencent.com> Cc: Andrea Righi <andrea@betterlinux.com> Cc: Fenggaung Wu <fengguang.wu@intel.com> Cc: Jinliang Zheng <alexjlzheng@tencent.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
idr_for_each() is protected by rwsem, but this is not enough. If it is
not protected by RCU read-critical region, when idr_for_each() calls
radix_tree_node_free() through call_rcu() to free the radix_tree_node
structure, the node will be freed immediately, and when reading the next
node in radix_tree_for_each_slot(), the already freed memory may be read.
Therefore, we need to add code to make sure that idr_for_each() is
protected within the RCU read-critical region when we call it in
shm_destroy_orphaned().
Link: https://lkml.kernel.org/r/20250424143322.18830-1-aha310510@gmail.com Fixes: b34a6b1da371 ("ipc: introduce shm_rmid_forced sysctl") Signed-off-by: Jeongjun Park <aha310510@gmail.com> Reported-by: syzbot+a2b84e569d06ca3a949c@syzkaller.appspotmail.com Cc: Jeongjun Park <aha310510@gmail.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SPICC is missing fclk_div2, which means fclk_div5 and fclk_div7 indexes
are wrong on this clock. This causes the spicc module to output sclk at
2.5x the expected rate when clock index 3 is picked.
Adding the missing fclk_div2 resolves this.
[jbrunet: amended commit description] Fixes: a18c8e0b7697 ("clk: meson: g12a: add support for the SPICC SCLK Source clocks") Cc: stable@vger.kernel.org # 6.1 Signed-off-by: Da Xue <da@libre.computer> Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Link: https://lore.kernel.org/r/20250512142617.2175291-1-da@libre.computer Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The decompressor is built with the default C dialect, which is now gnu23
on gcc-15, and this clashes with the kernel's bool type definition:
In file included from include/uapi/linux/posix_types.h:5,
from arch/parisc/boot/compressed/misc.c:7:
include/linux/stddef.h:11:9: error: cannot use keyword 'false' as enumeration constant
11 | false = 0,
Add the -std=gnu11 argument here, as we do for all other architectures.
Second to last potentially related work creation:
kasan_save_stack+0x20/0x40 mm/kasan/common.c:45
__kasan_record_aux_stack+0x94/0xa0 mm/kasan/generic.c:492
__call_rcu_common.constprop.0+0xc3/0xa10 kernel/rcu/tree.c:2713
netlink_release+0x620/0xc20 net/netlink/af_netlink.c:802
__sock_release+0xb5/0x270 net/socket.c:663
sock_close+0x1e/0x30 net/socket.c:1425
__fput+0x408/0xab0 fs/file_table.c:384
task_work_run+0x154/0x240 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:45 [inline]
do_exit+0x8e5/0x1320 kernel/exit.c:874
do_group_exit+0xcd/0x280 kernel/exit.c:1023
get_signal+0x1675/0x1850 kernel/signal.c:2905
arch_do_signal_or_restart+0x80/0x3b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x1b3/0x1e0 kernel/entry/common.c:218
do_syscall_64+0x66/0x110 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x78/0xe2
The buggy address belongs to the object at ffff88800f5be000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 2656 bytes to the right of
allocated 1280-byte region [ffff88800f5be000, ffff88800f5be500)
...
Memory state around the buggy address: ffff88800f5bee00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88800f5bee80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88800f5bef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^ ffff88800f5bef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88800f5bf000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
By analyzing the vmcore, we found that vc->vc_origin was somehow placed
one line prior to vc->vc_screenbuf when vc was in KD_TEXT mode, and
further writings to /dev/vcs caused out-of-bounds reads (and writes
right after) in vcs_write_buf_noattr().
Our further experiments show that in most cases, vc->vc_origin equals to
vga_vram_base when the console is in KD_TEXT mode, and it's around
vc->vc_screenbuf for the KD_GRAPHICS mode. But via triggerring a
TIOCL_SETVESABLANK ioctl beforehand, we can make vc->vc_origin be around
vc->vc_screenbuf while the console is in KD_TEXT mode, and then by
writing the special 'ESC M' control sequence to the tty certain times
(depends on the value of `vc->state.y - vc->vc_top`), we can eventually
move vc->vc_origin prior to vc->vc_screenbuf. Here's the PoC, tested on
QEMU:
```
int main() {
const int RI_NUM = 10; // should be greater than `vc->state.y - vc->vc_top`
int tty_fd, vcs_fd;
const char *tty_path = "/dev/tty0";
const char *vcs_path = "/dev/vcs";
const char escape_seq[] = "\x1bM"; // ESC + M
const char trigger_seq[] = "Let's trigger an OOB write.";
struct vt_sizes vt_size = { 70, 2 };
int blank = TIOCL_BLANKSCREEN;
If fb_add_videomode() in fb_set_var() fails to allocate memory for
fb_videomode, later it may lead to a null-ptr dereference in
fb_videomode_to_var(), as the fb_info is registered while not having the
mode in modelist that is expected to be there, i.e. the one that is
described in fb_info->var.
The reason is that fb_info->var is being modified in fb_set_var(), and
then fb_videomode_to_var() is called. If it fails to add the mode to
fb_info->modelist, fb_set_var() returns error, but does not restore the
old value of fb_info->var. Restore fb_info->var on failure the same way
it is done earlier in the function.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Setting tty->disc_data before opening the NCI device means we need to
clean it up on error paths. This also opens some short window if device
starts sending data, even before NCIUARTSETDRIVER IOCTL succeeded
(broken hardware?). Close the window by exposing tty->disc_data only on
the success path, when opening of the NCI device and try_module_get()
succeeds.
The code differs in error path in one aspect: tty->disc_data won't be
ever assigned thus NULL-ified. This however should not be relevant
difference, because of "tty->disc_data=NULL" in nci_uart_tty_open().
w/ below testcase, resize will generate a corrupted image which
contains inconsistent metadata, so when mounting such image, it
will trigger kernel panic:
sit_i->bitmap_size is 192, so size of sit bitmap is 192*8=1536, at maximum
there are 1536 sit blocks, however MAIN_SEGS is 261893, so that sit_blk_cnt
is 4762, build_sit_entries() -> current_sit_addr() tries to access
out-of-boundary in sit_bitmap at offset from [1536, 4762), once sit_bitmap
and sit_bitmap_mirror is not the same, it will trigger f2fs_bug_on().
Let's add sanity check in f2fs_sanity_check_ckpt() to avoid panic.
The "len" variable comes from the firmware and we generally do
trust firmware, but it's always better to double check. If the "len"
is too large it could result in memory corruption when we do
"memcpy(fragment->data, rec->data, len);"
There are several locations that get the correct maxbytes value based on
the inode's block type. It would be beneficial to extract a common
helper function to make the code more clear.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://patch.msgid.link/20250506012009.3896990-3-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Luis and David are reporting that after running generic/750 test for 90+
hours on 2k ext4 filesystem, they are able to trigger a warning in
jbd2_journal_dirty_metadata() complaining that there are not enough
credits in the running transaction started in ext4_do_writepages().
Indeed the code in ext4_do_writepages() is racy and the extent tree can
change between the time we compute credits necessary for extent tree
computation and the time we actually modify the extent tree. Thus it may
happen that the number of credits actually needed is higher. Modify
ext4_ext_index_trans_blocks() to count with the worst case of maximum
tree depth. This can reduce the possible number of writers that can
operate in the system in parallel (because the credit estimates now won't
fit in one transaction) but for reasonably sized journals this shouldn't
really be an issue. So just go with a safe and simple fix.
That happens because write_begin will succeed as when
ext4_generic_write_inline_data calls ext4_prepare_inline_data, pos + len
will be truncated, leading to ext4_prepare_inline_data parameter to be 6
instead of 0x10000000006.
Then, later when write_end is called, we hit:
BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);
at ext4_write_inline_data.
Fix it by using a loff_t type for the len parameter in
ext4_prepare_inline_data instead of an unsigned int.
The fsl-mc bus associated to the root DPRC in a DPAA2 system exports a
device file for userspace access to the MC firmware. In case the DPRC's
local MC portal (DPMCP) is currently in use, a new DPMCP device is
allocated through the fsl_mc_portal_allocate() function.
In this case, the call to fsl_mc_portal_allocate() will fail with -EINVAL
when trying to add a device link between the root DPRC (consumer) and
the newly allocated DPMCP device (supplier). This is because the DPMCP
is a dependent of the DPRC device (the bus).
Fix this by not adding a device link in case the DPMCP is allocated for
the root DPRC's usage.
The controller has a hardware bug that can hard hang the system when
doing ATAPI DMAs without any trace of what happened. Depending on the
device attached, it can also prevent the system from booting.
In this case, the system hangs when reading the ATIP from optical media
with cdrecord -vvv -atip on an _NEC DVD_RW ND-4571A 1-01 and an
Optiarc DVD RW AD-7200A 1.06 attached to an ASRock 990FX Extreme 4,
running at UDMA/33.
The issue can be reproduced by running the same command with a cygwin
build of cdrecord on WinXP, although it requires more attempts to cause
it. The hang in that case is also resolved by forcing PIO. It doesn't
appear that VIA has produced any drivers for that OS, thus no known
workaround exists.
HDDs attached to the controller do not suffer from any DMA issues.
When mhi_async_power_up() enables IRQs, it is possible that we could
receive a SYSERR notification from the device if the firmware has crashed
for some reason. Then the SYSERR notification queues a work item that
cannot execute until the pm_mutex is released by mhi_async_power_up().
So the SYSERR work item will be pending. If mhi_async_power_up() detects
the SYSERR, it will handle it. If the device is in PBL, then the PBL state
transition event will be queued, resulting in a work item after the
pending SYSERR work item. Once mhi_async_power_up() releases the pm_mutex,
the SYSERR work item can run. It will blindly attempt to reset the MHI
state machine, which is the recovery action for SYSERR. PBL/SBL are not
interrupt driven and will ignore the MHI Reset unless SYSERR is actively
advertised. This will cause the SYSERR work item to timeout waiting for
reset to be cleared, and will leave the host state in SYSERR processing.
The PBL transition work item will then run, and immediately fail because
SYSERR processing is not a valid state for PBL transition.
This leaves the device uninitialized.
This issue has a fairly unique signature in the kernel log:
mhi mhi3: Requested to power ON
Qualcomm Cloud AI 100 0000:36:00.0: Fatal error received from
device. Attempting to recover
mhi mhi3: Power on setup success
mhi mhi3: Device failed to exit MHI Reset state
mhi mhi3: Device MHI is not in valid state
We cannot remove the SYSERR handling from mhi_async_power_up() because the
device may be in the SYSERR state, but we missed the notification as the
irq was fired before irqs were enabled. We also can't queue the SYSERR work
item from mhi_async_power_up() if SYSERR is detected because that may
result in a duplicate work item, and cause the same issue since the
duplicate item will blindly issue MHI reset even if SYSERR is no longer
active.
Instead, add a check in the SYSERR work item to make sure that MHI reset is
only issued if the device is in SYSERR state for PBL or SBL EEs.
Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions") Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com> Signed-off-by: Jeff Hugo <jeff.hugo@oss.qualcomm.com> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Reviewed-by: Troy Hanson <quic_thanson@quicinc.com> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250328163526.3365497-1-jeff.hugo@oss.qualcomm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The late init call just writes to omap4 registers as soon as
CONFIG_MFD_CPCAP is enabled without checking whether the
cpcap driver is actually there or the SoC is indeed an
OMAP4.
Rather do these things only with the right device combination.
Fixes booting the BT200 with said configuration enabled and non-factory
X-Loader and probably also some surprising behavior on other devices.
Fixes: c145649bf262 ("ARM: OMAP2+: Configure voltage controller for cpcap to low-speed") CC: stable@vger.kernel.org Signed-off-by: Andreas Kemnade <andreas@kemnade.info> Reivewed-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20250331144439.769697-1-andreas@kemnade.info Signed-off-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 260364d112bc ("arm[64]/memremap: don't abuse pfn_valid() to ensure
presence of linear map") added the definition of
arch_memremap_can_ram_remap() for arm[64] specific filtering of what pages
can be used from the linear mapping. memblock_is_map_memory() was called
with the pfn of the address given to arch_memremap_can_ram_remap();
however, memblock_is_map_memory() expects to be given an address for arm,
not a pfn.
This results in calls to memremap() returning a newly mapped area when
it should return an address in the existing linear mapping.
Fix this by removing the address to pfn translation and pass the
address directly.
Fixes: 260364d112bc ("arm[64]/memremap: don't abuse pfn_valid() to ensure presence of linear map") Signed-off-by: Ross Stutterheim <ross.stutterheim@garmin.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: stable@vger.kernel.org Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
BUG: KASAN: vmalloc-out-of-bounds in tpg_fill_plane_pattern drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:2608 [inline]
BUG: KASAN: vmalloc-out-of-bounds in tpg_fill_plane_buffer+0x1a9c/0x5af0 drivers/media/common/v4l2-tpg/v4l2-tpg-core.c:2705
Write of size 1440 at addr ffffc9000d0ffda0 by task vivid-000-vid-c/5304
CPU: 0 UID: 0 PID: 5304 Comm: vivid-000-vid-c Not tainted 6.14.0-rc2-syzkaller-00039-g09fbf3d50205 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
syzbot reported a slab-use-after-free Read in vidtv_mux_init. [1]
After PSI initialization fails, the si member is accessed again, resulting
in this uaf.
After si initialization fails, the subsequent process needs to be exited.
[1]
BUG: KASAN: slab-use-after-free in vidtv_mux_pid_ctx_init drivers/media/test-drivers/vidtv/vidtv_mux.c:78 [inline]
BUG: KASAN: slab-use-after-free in vidtv_mux_init+0xac2/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:524
Read of size 8 at addr ffff88802fa42acc by task syz.2.37/6059
Use common wrappers operating directly on the struct sg_table objects to
fix incorrect use of scatterlists sync calls. dma_sync_sg_for_*()
functions have to be called with the number of elements originally passed
to dma_map_sg_*() function, not the one returned in sgt->nents.
Fixes: d4db5eb57cab ("media: videobuf2: add begin/end cpu_access callbacks to dma-sg") CC: stable@vger.kernel.org Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Tomasz Figa <tfiga@chromium.org> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Video device registering has been moved earlier in the probe function,
but the new order has not been propagated to error handling. This means
we can end with unreleased resources on error (e.g dangling video device
on missing firmware probe aborting).
Once device_register() failed, we should call put_device() to
decrement reference count for cleanup. Or it could cause memory leak.
And move callback function v4l2_device_release() and v4l2_device_get()
before put_device().
As comment of device_register() says, 'NOTE: _Never_ directly free
@dev after calling this function, even if it returned an error! Always
use put_device() to give up the reference initialized in this function
instead.'
Found by code review.
Cc: stable@vger.kernel.org Fixes: dc93a70cc7f9 ("V4L/DVB (9973): v4l2-dev: use the release callback from device instead of cdev") Signed-off-by: Ma Ke <make24@iscas.ac.cn> Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In hdcs_init(), the return value of stv06xx_read_sensor() needs to be
checked. A proper implementation can be found in vv6410_dump(). Add a
check in loop condition and propergate error code to fix this issue.
syzbot reported a uninit-value in cxusb_i2c_xfer. [1]
Only when the write operation of usb_bulk_msg() in dvb_usb_generic_rw()
succeeds and rlen is greater than 0, the read operation of usb_bulk_msg()
will be executed to read rlen bytes of data from the dvb device into the
rbuf.
In this case, although rlen is 1, the write operation failed which resulted
in the dvb read operation not being executed, and ultimately variable i was
not initialized.
RTL8723BE found on some ASUSTek laptops, such as F441U and X555UQ with
subsystem ID 11ad:1723 are known to output large amounts of PCIe AER
errors during and after boot up, causing heavy lags and at times lock-ups:
pcieport 0000:00:1c.5: AER: Correctable error message received from 0000:00:1c.5
pcieport 0000:00:1c.5: PCIe Bus Error: severity=Correctable, type=Physical Layer, (Receiver ID)
pcieport 0000:00:1c.5: device [8086:9d15] error status/mask=00000001/00002000
pcieport 0000:00:1c.5: [ 0] RxErr
Disable ASPM on this combo as a quirk.
This patch is a revision of a previous patch (linked below) which
attempted to disable ASPM for RTL8723BE on all Intel Skylake and Kaby Lake
PCIe bridges. I take a more conservative approach as all known reports
point to ASUSTek laptops of these two generations with this particular
wireless card.
Please note, however, before the rtl8723be finishes probing, the AER
errors remained. After the module finishes probing, all AER errors would
indeed be eliminated, along with heavy lags, poor network throughput,
and/or occasional lock-ups.
In nfs4_state_start_net(), laundromat_work may access nfsd_ssc through
nfs4_laundromat -> nfsd4_ssc_expire_umount. If nfsd_ssc isn't initialized,
this can cause NULL pointer dereference.
Normally the delayed start of laundromat_work allows sufficient time for
nfsd_ssc initialization to complete. However, when the kernel waits too
long for userspace responses (e.g. in nfs4_state_start_net ->
nfsd4_end_grace -> nfsd4_record_grace_done -> nfsd4_cld_grace_done ->
cld_pipe_upcall -> __cld_pipe_upcall -> wait_for_completion path), the
delayed work may start before nfsd_ssc initialization finishes.
Fix this by moving nfsd_ssc initialization before starting laundromat_work.
Fixes: f4e44b393389 ("NFSD: delay unmount source's export after inter-server copy completed.") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|If a malicious USB device pretends to be an Intersil p54 wifi
|interface and generates an eeprom_readback message with a large
|eeprom->v1.len, p54_rx_eeprom_readback() will copy data from the
|message beyond the end of priv->eeprom.
|
|static void p54_rx_eeprom_readback(struct p54_common *priv,
| struct sk_buff *skb)
|{
| struct p54_hdr *hdr = (struct p54_hdr *) skb->data;
| struct p54_eeprom_lm86 *eeprom = (struct p54_eeprom_lm86 *) hdr->data;
|
| if (priv->fw_var >= 0x509) {
| memcpy(priv->eeprom, eeprom->v2.data,
| le16_to_cpu(eeprom->v2.len));
| } else {
| memcpy(priv->eeprom, eeprom->v1.data,
| le16_to_cpu(eeprom->v1.len));
| }
| [...]
The eeprom->v{1,2}.len is set by the driver in p54_download_eeprom().
The device is supposed to provide the same length back to the driver.
But yes, it's possible (like shown in the report) to alter the value
to something that causes a crash/panic due to overrun.
This patch addresses the issue by adding the size to the common device
context, so p54_rx_eeprom_readback no longer relies on possibly tampered
values... That said, it also checks if the "firmware" altered the value
and no longer copies them.
The one, small saving grace is: Before the driver tries to read the eeprom,
it needs to upload >a< firmware. the vendor firmware has a proprietary
license and as a reason, it is not present on most distributions by
default.
Cc: <stable@kernel.org> Reported-by: Robert Morris <rtm@mit.edu> Closes: https://lore.kernel.org/linux-wireless/28782.1747258414@localhost/ Fixes: 7cb770729ba8 ("p54: move eeprom code into common library") Signed-off-by: Christian Lamparter <chunkeey@gmail.com> Link: https://patch.msgid.link/20250516184107.47794-1-chunkeey@gmail.com Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function mlx5_query_nic_vport_node_guid() calls the function
mlx5_query_nic_vport_context() but does not check its return value.
A proper implementation can be found in mlx5_nic_vport_query_local_lb().
Add error handling for mlx5_query_nic_vport_context(). If it fails, free
the out buffer via kvfree() and return error code.
The function mlx5_query_nic_vport_qkey_viol_cntr() calls the function
mlx5_query_nic_vport_context() but does not check its return value. This
could lead to undefined behavior if the query fails. A proper
implementation can be found in mlx5_nic_vport_query_local_lb().
Add error handling for mlx5_query_nic_vport_context(). If it fails, free
the out buffer via kvfree() and return error code.
Commit c141ecc3cecd ("of: Warn when of_property_read_bool() is used on
non-boolean properties") added a warning when trying to parse a property
with a value (boolean properties are defined as: absent = false, present
without any value = true). This causes a warning from meson-card-utils.
meson-card-utils needs to know about the existence of the
"audio-routing" and/or "audio-widgets" properties in order to properly
parse them. Switch to of_property_present() in order to silence the
following warning messages during boot:
OF: /sound: Read of boolean property 'audio-routing' with a value.
OF: /sound: Read of boolean property 'audio-widgets' with a value.
Fixes: 7864a79f37b5 ("ASoC: meson: add axg sound card support") Tested-by: Christian Hewitt <christianshewitt@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Link: https://patch.msgid.link/20250419213448.59647-1-martin.blumenstingl@googlemail.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The function sdm845_slim_snd_hw_params() calls the functuion
snd_soc_dai_set_channel_map() but does not check its return
value. A proper implementation can be found in msm_snd_hw_params().
Add error handling for snd_soc_dai_set_channel_map(). If the
function fails and it is not a unsupported error, return the
error code immediately.
Fixes: 5caf64c633a3 ("ASoC: qcom: sdm845: add support to DB845c and Lenovo Yoga") Cc: stable@vger.kernel.org # v5.6 Signed-off-by: Wentao Liang <vulab@iscas.ac.cn> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Link: https://patch.msgid.link/20250519075739.1458-1-vulab@iscas.ac.cn Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch moves the msleep_interruptible() out of the non-sleepable
context by moving the ls->ls_recover_spin spinlock around so
msleep_interruptible() will be called in a sleepable context.
Cc: stable@vger.kernel.org Fixes: 4a7727725dc7 ("GFS2: Fix recovery issues for spectators") Suggested-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This driver tries to chain requests together before submitting them
to hardware in order to reduce completion interrupts.
However, it even extends chains that have already been submitted
to hardware. This is dangerous because there is no way of knowing
whether the hardware has already read the DMA memory in question
or not.
Fix this by splitting the chain list into two. One for submitted
requests and one for requests that have not yet been submitted.
Only extend the latter.
Reported-by: Klaus Kudielka <klaus.kudielka@gmail.com> Fixes: 85030c5168f1 ("crypto: marvell - Add support for chaining crypto requests in TDMA mode") Cc: <stable@vger.kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
populate_attrs() may override failure for creating attribute files
by success for creating subsequent bin attribute files, and have
wrong return value.
Fix by creating bin attribute files under successfully creating
attribute files.
Fixes: 03607ace807b ("configfs: implement binary attributes") Cc: stable@vger.kernel.org Reviewed-by: Joel Becker <jlbec@evilplan.org> Reviewed-by: Breno Leitao <leitao@debian.org> Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com> Link: https://lore.kernel.org/r/20250507-fix_configfs-v3-2-fe2d96de8dc4@quicinc.com Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
My prior cleanup missed that tcp_data_ready() has to look at SOCK_DONE.
Otherwise, an application using SO_RCVLOWAT will not get EPOLLIN event
if a FIN is received in the middle of expected payload.
The reason SOCK_DONE is not examined in tcp_epollin_ready()
is that tcp_poll() catches the FIN because tcp_fin()
is also setting RCV_SHUTDOWN into sk->sk_shutdown
Fixes: 05dc72aba364 ("tcp: factorize logic into tcp_epollin_ready()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Wei Wang <weiwan@google.com> Cc: Arjun Roy <arjunroy@google.com> Reviewed-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The headercheck tries to call clang with a mix of compiler arguments
that don't include the target architecture. When building e.g. x86
headers on arm64, this produces a warning like
scripts/Makefile.clang was changed in the linked commit to move --target from
KBUILD_CFLAGS to KBUILD_CPPFLAGS, as that generally has a broader scope.
However that variable is not inspected by the userprogs logic,
breaking cross compilation on clang.
Use both variables to detect bitsize and target arguments for userprogs.
If we sanitize error returns, the debug statements need
to come before that so that we don't lose information.
Signed-off-by: Oliver Neukum <oneukum@suse.com> Fixes: 405b0d610745 ("net: usb: aqc111: fix error handling of usbnet read calls") Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
io_bitmap_exit() is invoked from exit_thread() when a task exists or
when a fork fails. In the latter case the exit_thread() cleans up
resources which were allocated during fork().
io_bitmap_exit() invokes task_update_io_bitmap(), which in turn ends up
in tss_update_io_bitmap(). tss_update_io_bitmap() operates on the
current task. If current has TIF_IO_BITMAP set, but no bitmap installed,
tss_update_io_bitmap() crashes with a NULL pointer dereference.
There are two issues, which lead to that problem:
1) io_bitmap_exit() should not invoke task_update_io_bitmap() when
the task, which is cleaned up, is not the current task. That's a
clear indicator for a cleanup after a failed fork().
2) A task should not have TIF_IO_BITMAP set and neither a bitmap
installed nor IOPL emulation level 3 activated.
This happens when a kernel thread is created in the context of
a user space thread, which has TIF_IO_BITMAP set as the thread
flags are copied and the IO bitmap pointer is cleared.
Other than in the failed fork() case this has no impact because
kernel threads including IO workers never return to user space and
therefore never invoke tss_update_io_bitmap().
Cure this by adding the missing cleanups and checks:
1) Prevent io_bitmap_exit() to invoke task_update_io_bitmap() if
the to be cleaned up task is not the current task.
2) Clear TIF_IO_BITMAP in copy_thread() unconditionally. For user
space forks it is set later, when the IO bitmap is inherited in
io_bitmap_share().
For paranoia sake, add a warning into tss_update_io_bitmap() to catch
the case, when that code is invoked with inconsistent state.
Fixes: ea5f1cd7ab49 ("x86/ioperm: Remove bitmap if all permissions dropped") Reported-by: syzbot+e2b1803445d236442e54@syzkaller.appspotmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/87wmdceom2.ffs@tglx Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dm_op hypercalls might come from userspace and pass memory addresses as
parameters. The memory addresses typically correspond to buffers
allocated in userspace to hold extra hypercall parameters.
On ARM, when CONFIG_ARM64_SW_TTBR0_PAN is enabled, they might not be
accessible by Xen, as a result ioreq hypercalls might fail. See the
existing comment in arch/arm64/xen/hypercall.S regarding privcmd_call
for reference.
For privcmd_call, Linux calls uaccess_ttbr0_enable before issuing the
hypercall thanks to commit 9cf09d68b89a. We need to do the same for
dm_op. This resolves the problem.
usb core avoids sending a Set-Interface altsetting 0 request after device
reset, and instead relies on calling usb_disable_interface() and
usb_enable_interface() to flush and reset host-side of those endpoints.
xHCI hosts allocate and set up endpoint ring buffers and host_ep->hcpriv
during usb_hcd_alloc_bandwidth() callback, which in this case is called
before flushing the endpoint in usb_disable_interface().
Call usb_disable_interface() before usb_hcd_alloc_bandwidth() to ensure
URBs are flushed before new ring buffers for the endpoints are allocated.
Otherwise host driver will attempt to find and remove old stale URBs
from a freshly allocated new ringbuffer.
drm/amd/display: Do not add '-mhard-float' to dcn2{1,0}_resource.o for clang
This patch is for linux-5.15.y and earlier only. It is functionally
equivalent to upstream commit 7db038d9790e ("drm/amd/display: Do not add
'-mhard-float' to dml_ccflags for clang"), which was created after all
files that require '-mhard-float' were moved under the dml folder. In
kernels older than 5.18, which do not contain upstream commits
22f87d998326 ("drm/amd/display: move FPU operations from dcn21 to dml/dcn20 folder") cf689e869cf0 ("drm/amd/display: move FPU-related code from dcn20 to dml folder")
After commit feb843a469fb ("kbuild: add $(CLANG_FLAGS) to
KBUILD_CPPFLAGS"), there is an error while building certain PowerPC
assembly files with clang:
arch/powerpc/lib/copypage_power7.S: Assembler messages:
arch/powerpc/lib/copypage_power7.S:34: Error: junk at end of line: `0b01000'
arch/powerpc/lib/copypage_power7.S:35: Error: junk at end of line: `0b01010'
arch/powerpc/lib/copypage_power7.S:37: Error: junk at end of line: `0b01000'
arch/powerpc/lib/copypage_power7.S:38: Error: junk at end of line: `0b01010'
arch/powerpc/lib/copypage_power7.S:40: Error: junk at end of line: `0b01010'
clang: error: assembler command failed with exit code 1 (use -v to see invocation)
as-option only uses KBUILD_AFLAGS, so after removing CLANG_FLAGS from
KBUILD_AFLAGS, there is no more '--target=' or '--prefix=' flags. As a
result of those missing flags, the host target
will be tested during as-option calls and likely fail, meaning necessary
flags may not get added when building assembly files, resulting in
errors like seen above.
Add KBUILD_CPPFLAGS to as-option invocations to clear up the errors.
This should have been done in commit d5c8d6e0fa61 ("kbuild: Update
assembler calls to use proper flags and language target"), which
switched from using the assembler target to the assembler-with-cpp
target, so flags that affect preprocessing are passed along in all
relevant tests. as-option now mirrors cc-option.
A future change will move CLANG_FLAGS from KBUILD_{A,C}FLAGS to
KBUILD_CPPFLAGS so that '--target' is available while preprocessing.
When that occurs, the following errors appear multiple times when
building ARCH=powerpc powernv_defconfig:
ld.lld: error: vmlinux.a(arch/powerpc/kernel/head_64.o):(.text+0x12d4): relocation R_PPC64_ADDR16_HI out of range: -4611686018409717520 is not in [-2147483648, 2147483647]; references '__start___soft_mask_table'
ld.lld: error: vmlinux.a(arch/powerpc/kernel/head_64.o):(.text+0x12e8): relocation R_PPC64_ADDR16_HI out of range: -4611686018409717392 is not in [-2147483648, 2147483647]; references '__stop___soft_mask_table'
Diffing the .o.cmd files reveals that -DHAVE_AS_ATHIGH=1 is not present
anymore, because as-instr only uses KBUILD_AFLAGS, which will no longer
contain '--target'.
Mirror Kconfig's as-instr and add CLANG_FLAGS explicitly to the
invocation to ensure the target information is always present.
A future change will move CLANG_FLAGS from KBUILD_{A,C}FLAGS to
KBUILD_CPPFLAGS so that '--target' is available while preprocessing.
When that occurs, the following error appears when building ARCH=mips
with clang (tip of tree error shown):
clang: error: unsupported option '-mabi=' for target 'x86_64-pc-linux-gnu'
Add KBUILD_CPPFLAGS in the CHECKFLAGS invocation to keep everything
working after the move.
When clang's -Qunused-arguments is dropped from KBUILD_CPPFLAGS, it
warns:
clang-16: error: argument unused during compilation: '-mhard-float' [-Werror,-Wunused-command-line-argument]
Similar to commit 84edc2eff827 ("selftest/fpu: avoid clang warning"),
just add this flag to GCC builds. Commit 0f0727d971f6 ("drm/amd/display:
readd -msse2 to prevent Clang from emitting libcalls to undefined SW FP
routines") added '-msse2' to prevent clang from emitting software
floating point routines.
Signed-off-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Alex Deucher <alexander.deucher@amd.com> Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
as-instr uses KBUILD_AFLAGS, but as-option uses KBUILD_CFLAGS. This can
cause as-option to fail unexpectedly when CONFIG_WERROR is set, because
clang will emit -Werror,-Wunused-command-line-argument for various -m
and -f flags in KBUILD_CFLAGS for assembler sources.
Callers of as-option and as-instr should be adding flags to
KBUILD_AFLAGS / aflags-y, not KBUILD_CFLAGS / cflags-y. Use
KBUILD_AFLAGS in all macros to clear up the initial problem.
Unfortunately, -Wunused-command-line-argument can still be triggered
with clang by the presence of warning flags or macro definitions because
'-x assembler' is used, instead of '-x assembler-with-cpp', which will
consume these flags. Switch to '-x assembler-with-cpp' in places where
'-x assembler' is used, as the compiler is always used as the driver for
out of line assembler sources in the kernel.
Finally, add -Werror to these macros so that they behave consistently
whether or not CONFIG_WERROR is set.
[nathan: Reworded and expanded on problems in commit message
Use '-x assembler-with-cpp' in a couple more places]
A future change will switch as-option to use KBUILD_AFLAGS instead of
KBUILD_CFLAGS to allow clang to drop -Qunused-arguments, which may cause
issues if the flag being tested requires a flag previously added to
KBUILD_CFLAGS but not KBUILD_AFLAGS. Use cc-option for cflags additions
so that the flags are tested properly.
Signed-off-by: Nathan Chancellor <nathan@kernel.org> Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Tested-by: Linux Kernel Functional Testing <lkft@linaro.org> Tested-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MIPS: Move '-Wa,-msoft-float' check from as-option to cc-option
This patch is for linux-6.1.y and earlier, it has no direct mainline
equivalent.
In order to backport commit d5c8d6e0fa61 ("kbuild: Update assembler
calls to use proper flags and language target") to resolve a separate
issue regarding PowerPC, the problem noticed and fixed by
commit 80a20d2f8288 ("MIPS: Always use -Wa,-msoft-float and eliminate
GAS_HAS_SET_HARDFLOAT") needs to be addressed. Unfortunately, 6.1 and
earlier do not contain commit e4412739472b ("Documentation: raise
minimum supported version of binutils to 2.25"), so it cannot be assumed
that all supported versions of GNU as have support for -msoft-float.
In order to switch from KBUILD_CFLAGS to KBUILD_AFLAGS in as-option
without consequence, move the '-Wa,-msoft-float' check to cc-option,
including '$(cflags-y)' directly to avoid the issue mentioned in
commit 80a20d2f8288 ("MIPS: Always use -Wa,-msoft-float and eliminate
GAS_HAS_SET_HARDFLOAT").
as-option tests new options using KBUILD_CFLAGS, which causes problems
when using as-option to update KBUILD_AFLAGS because many compiler
options are not valid assembler options.
This will be fixed in a follow up patch. Before doing so, move the
assembler test for -Wa,-mrelax-relocations=no from using as-option to
cc-option.
If an exiting non-autoreaping task has already passed exit_notify() and
calls handle_posix_cpu_timers() from IRQ, it can be reaped by its parent
or debugger right after unlock_task_sighand().
If a concurrent posix_cpu_timer_del() runs at that moment, it won't be
able to detect timer->it.cpu.firing != 0: cpu_timer_task_rcu() and/or
lock_task_sighand() will fail.
Add the tsk->exit_state check into run_posix_cpu_timers() to fix this.
This fix is not needed if CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y, because
exit_task_work() is called before exit_notify(). But the check still
makes sense, task_work_add(&tsk->posix_cputimers_work.work) will fail
anyway in this case.
Calling qdisc_purge_queue() instead of qdisc_tree_flush_backlog()
should fix the race, because all packets will be purged from the qdisc
before releasing the lock.
Fixes: b05972f01e7d ("net: sched: tbf: don't call qdisc_put() while holding tree lock") Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Suggested-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250611111515.1983366-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
est_qlen_notify() deletes its class from its active list with
list_del() when qlen is 0, therefore, it is not idempotent and
not friendly to its callers, like fq_codel_dequeue().
Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers'
life. Also change other list_del()'s to list_del_init() just to be
extra safe.
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Link: https://patch.msgid.link/20250403211033.166059-6-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stable-dep-of: d92adacdd8c2 ("net_sched: ets: fix a race in ets_qdisc_change()") Signed-off-by: Sasha Levin <sashal@kernel.org>
Calling qdisc_purge_queue() instead of qdisc_tree_flush_backlog()
should fix the race, because all packets will be purged from the qdisc
before releasing the lock.
Fixes: b05972f01e7d ("net: sched: tbf: don't call qdisc_put() while holding tree lock") Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Suggested-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Zhengchao Shao <shaozhengchao@huawei.com> Link: https://patch.msgid.link/20250611111515.1983366-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Calling qdisc_purge_queue() instead of qdisc_tree_flush_backlog()
should fix the race, because all packets will be purged from the qdisc
before releasing the lock.
Fixes: 0c8d13ac9607 ("net: sched: red: delay destroying child qdisc on replace") Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Suggested-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250611111515.1983366-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Calling qdisc_purge_queue() instead of qdisc_tree_flush_backlog()
should fix the race, because all packets will be purged from the qdisc
before releasing the lock.
Fixes: 7b8e0b6e6599 ("net: sched: prio: delay destroying child qdiscs on change") Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Suggested-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250611111515.1983366-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
When attempting to add a rule to an existing flow group, if a matching
flow group exists but is not active, the error code returned should be
EAGAIN, so that the rule can be added to the matching flow group once
it is active, rather than ENOENT, which indicates that no matching
flow group was found.
Fixes: bd71b08ec2ee ("net/mlx5: Support multiple updates of steering rules in parallel") Signed-off-by: Gavi Teitz <gavi@nvidia.com> Signed-off-by: Roi Dayan <roid@nvidia.com> Signed-off-by: Patrisious Haddad <phaddad@nvidia.com> Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Signed-off-by: Mark Bloch <mbloch@nvidia.com> Link: https://patch.msgid.link/20250610151514.1094735-4-mbloch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
When firmware asks the driver to allocate more pages, using event of
give_pages, the driver should always allocate it from same NUMA, the
original device NUMA. Current code uses dev_to_node() which can result
in different NUMA as it is changed by other driver flows, such as
mlx5_dma_zalloc_coherent_node(). Instead, use saved numa node for
allocating firmware pages.
Fixes: 311c7c71c9bb ("net/mlx5e: Allocate DMA coherent memory on reader NUMA node") Signed-off-by: Moshe Shemesh <moshe@nvidia.com> Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Signed-off-by: Mark Bloch <mbloch@nvidia.com> Link: https://patch.msgid.link/20250610151514.1094735-2-mbloch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
When using publicly available tools like 'mdio-tools' to read/write data
from/to network interface and its PHY via mdiobus, there is no verification of
parameters passed to the ioctl and it accepts any mdio address.
Currently there is support for 32 addresses in kernel via PHY_MAX_ADDR define,
but it is possible to pass higher value than that via ioctl.
While read/write operation should generally fail in this case,
mdiobus provides stats array, where wrong address may allow out-of-bounds
read/write.
Fix that by adding address verification before read/write operation.
While this excludes this access from any statistics, it improves security of
read/write operation.
Fixes: 080bb352fad00 ("net: phy: Maintain MDIO device and bus statistics") Signed-off-by: Jakub Raczynski <j.raczynski@samsung.com> Reported-by: Wenjing Shan <wenjing.shan@samsung.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
When performing a C22 operation, check that the bus driver actually
provides the methods, and return -EOPNOTSUPP if not. C45 only busses
do exist, and in future their C22 methods will be NULL.
Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 0e629694126c ("net/mdiobus: Fix potential out-of-bounds read/write access") Signed-off-by: Sasha Levin <sashal@kernel.org>
According to 802.1AE standard, when ES and SC flags in TCI are zero,
used SCI should be the current active SC_RX. Current code uses the
header MAC address. Without this patch, when ES flag is 0 (using a
bridge or switch), header MAC will not fit the SCI and MACSec frames
will be discarted.
In order to test this issue, MACsec link should be stablished between
two interfaces, setting SC and ES flags to zero and a port identifier
different than one. For example, using ip macsec tools:
ip link add link $ETH0 macsec0 type macsec port 11 send_sci off
end_station off
ip macsec add macsec0 tx sa 0 pn 2 on key 01 $ETH1_KEY
ip macsec add macsec0 rx port 11 address $ETH1_MAC
ip macsec add macsec0 rx port 11 address $ETH1_MAC sa 0 pn 2 on key 02
ip link set dev macsec0 up
ip link add link $ETH1 macsec1 type macsec port 11 send_sci off
end_station off
ip macsec add macsec1 tx sa 0 pn 2 on key 01 $ETH0_KEY
ip macsec add macsec1 rx port 11 address $ETH0_MAC
ip macsec add macsec1 rx port 11 address $ETH0_MAC sa 0 pn 2 on key 02
ip link set dev macsec1 up
Fixes: c09440f7dcb3 ("macsec: introduce IEEE 802.1AE driver") Co-developed-by: Andreu Montiel <Andreu.Montiel@technica-engineering.de> Signed-off-by: Andreu Montiel <Andreu.Montiel@technica-engineering.de> Signed-off-by: Carlos Fernandez <carlos.fernandez@technica-engineering.de> Reviewed-by: Subbaraya Sundeep <sbhatta@marvell.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
sk->sk_prot->sock_is_readable is a valid function pointer when sk resides
in a sockmap. After the last sk_psock_put() (which usually happens when
socket is removed from sockmap), sk->sk_prot gets restored and
sk->sk_prot->sock_is_readable becomes NULL.
This makes sk_is_readable() racy, if the value of sk->sk_prot is reloaded
after the initial check. Which in turn may lead to a null pointer
dereference.
Ensure the function pointer does not turn NULL after the check.
Fixes: 8934ce2fd081 ("bpf: sockmap redirect ingress support") Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Michal Luczaj <mhal@rbox.co> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250609-skisreadable-toctou-v1-1-d0dfb2d62c37@rbox.co Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
The proto ops ->stream_memory_read() is currently only used
by TCP to check whether psock queue is empty or not. We need
to rename it before reusing it for non-TCP protocols, and
adjust the exsiting users accordingly.
As suggested by John, clean up sockmap related Kconfigs:
Reduce the scope of CONFIG_BPF_STREAM_PARSER down to TCP stream
parser, to reflect its name.
Make the rest sockmap code simply depend on CONFIG_BPF_SYSCALL
and CONFIG_INET, the latter is still needed at this point because
of TCP/UDP proto update. And leave CONFIG_NET_SOCK_MSG untouched,
as it is used by non-sockmap cases.
Signed-off-by: Cong Wang <cong.wang@bytedance.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Lorenz Bauer <lmb@cloudflare.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20210223184934.6054-2-xiyou.wangcong@gmail.com
Stable-dep-of: 2660a544fdc0 ("net: Fix TOCTOU issue in sk_is_readable()") Signed-off-by: Sasha Levin <sashal@kernel.org>
Both tcp_data_ready() and tcp_stream_is_readable() share the same logic.
Add tcp_epollin_ready() helper to avoid duplication.
Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Arjun Roy <arjunroy@google.com> Cc: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 2660a544fdc0 ("net: Fix TOCTOU issue in sk_is_readable()") Signed-off-by: Sasha Levin <sashal@kernel.org>
When a VFLR interrupt is received during a VF reset initiated from a
different source, the VFLR may be not fully handled. This can
leave the VF in an undefined state.
To address this, set the I40E_VFLR_EVENT_PENDING bit again during VFLR
handling if the reset is not yet complete. This ensures the driver
will properly complete the VF reset in such scenarios.
Fixes: 52424f974bc5 ("i40e: Fix VF hang when reset is triggered on another VF") Signed-off-by: Robert Malz <robert.malz@canonical.com> Tested-by: Rafal Romanowski <rafal.romanowski@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
The function i40e_vc_reset_vf attempts, up to 20 times, to handle a
VF reset request, using the return value of i40e_reset_vf as an indicator
of whether the reset was successfully triggered. Currently, i40e_reset_vf
always returns true, which causes new reset requests to be ignored if a
different VF reset is already in progress.
This patch updates the return value of i40e_reset_vf to reflect when
another VF reset is in progress, allowing the caller to properly use
the retry mechanism.
Fixes: 52424f974bc5 ("i40e: Fix VF hang when reset is triggered on another VF") Signed-off-by: Robert Malz <robert.malz@canonical.com> Tested-by: Rafal Romanowski <rafal.romanowski@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
The user space calls mmap() to map VAS window paste address
and the kernel returns the complete mapped page for each
window. So return -EINVAL if non-zero is passed for offset
parameter to mmap().
See Documentation/arch/powerpc/vas-api.rst for mmap()
restrictions.
Co-developed-by: Jonathan Greental <yonatan02greental@gmail.com> Signed-off-by: Jonathan Greental <yonatan02greental@gmail.com> Reported-by: Jonathan Greental <yonatan02greental@gmail.com> Fixes: dda44eb29c23 ("powerpc/vas: Add VAS user space API") Signed-off-by: Haren Myneni <haren@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20250610021227.361980-2-maddy@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
The pseries platform will share vas and nx code and interfaces
with the PowerNV platform, so create the
arch/powerpc/platforms/book3s/ directory and move VAS API code
there. Functionality is not changed.
SFQ has an assumption of always being able to queue at least one packet.
However, after the blamed commit, sch->q.len can be inflated by packets
in sch->gso_skb, and an enqueue() on an empty SFQ qdisc can be followed
by an immediate drop.
Fix sfq_drop() to properly clear q->tail in this situation.
Tested:
ip netns add lb
ip link add dev to-lb type veth peer name in-lb netns lb
ethtool -K to-lb tso off # force qdisc to requeue gso_skb
ip netns exec lb ethtool -K in-lb gro on # enable NAPI
ip link set dev to-lb up
ip -netns lb link set dev in-lb up
ip addr add dev to-lb 192.168.20.1/24
ip -netns lb addr add dev in-lb 192.168.20.2/24
tc qdisc replace dev to-lb root sfq limit 100
scsi_host_put() is not required when shost is NULL, so jumping to the
correct label avoids unnecessary operations. These functions previously
jumped to the wrong goto label (put_host), which did not match the
intended cleanup logic.
Use the correct exit labels (exit_new_fnode, exit_del_fnode, etc.) to
ensure proper error handling. Also remove the unused put_host label
under iscsi_new_flashnode() as it is no longer needed.
No functional changes beyond accurate error path correction.
Fixes: c6a4bb2ef596 ("[SCSI] scsi_transport_iscsi: Add flash node mgmt support") Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com> Link: https://lore.kernel.org/r/20250530193012.3312911-1-alok.a.tiwari@oracle.com Reviewed-by: Mike Christie <michael.christie@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
In ath10k_snoc_hif_stop() we skip disabling the IRQs in the crash
recovery flow, but we still unconditionally call enable again in
ath10k_snoc_hif_start().
We can't check the ATH10K_FLAG_CRASH_FLUSH bit since it is cleared
before hif_start() is called, so instead check the
ATH10K_SNOC_FLAG_RECOVERY flag and skip enabling the IRQs during crash
recovery.
This fixes unbalanced IRQ enable splats that happen after recovering from
a crash.
Fixes: 0e622f67e041 ("ath10k: add support for WCN3990 firmware crash recovery") Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org> Tested-by: Loic Poulain <loic.poulain@oss.qualcomm.com> Link: https://patch.msgid.link/20250318205043.1043148-1-caleb.connolly@linaro.org Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
It happened "Kernel panic - not syncing: hung_task: blocked tasks" when
test simulate crash and ifconfig down/rmmod meanwhile.
Test steps:
1.Test commands, either can reproduce the hang for PCIe, SDIO and SNOC.
echo soft > /sys/kernel/debug/ieee80211/phy0/ath10k/simulate_fw_crash;sleep 0.05;ifconfig wlan0 down
echo soft > /sys/kernel/debug/ieee80211/phy0/ath10k/simulate_fw_crash;rmmod ath10k_sdio
echo hw-restart > /sys/kernel/debug/ieee80211/phy0/ath10k/simulate_fw_crash;rmmod ath10k_pci
2. dmesg:
[ 5622.548630] ath10k_sdio mmc1:0001:1: simulating soft firmware crash
[ 5622.655995] ieee80211 phy0: Hardware restart was requested
[ 5776.355164] INFO: task shill:1572 blocked for more than 122 seconds.
[ 5776.355687] INFO: task kworker/1:2:24437 blocked for more than 122 seconds.
[ 5776.359812] Kernel panic - not syncing: hung_task: blocked tasks
[ 5776.359836] CPU: 1 PID: 55 Comm: khungtaskd Tainted: G W 4.19.86 #137
[ 5776.359846] Hardware name: MediaTek krane sku176 board (DT)
[ 5776.359855] Call trace:
[ 5776.359868] dump_backtrace+0x0/0x170
[ 5776.359881] show_stack+0x20/0x2c
[ 5776.359896] dump_stack+0xd4/0x10c
[ 5776.359916] panic+0x12c/0x29c
[ 5776.359937] hung_task_panic+0x0/0x50
[ 5776.359953] kthread+0x120/0x130
[ 5776.359965] ret_from_fork+0x10/0x18
[ 5776.359986] SMP: stopping secondary CPUs
[ 5776.360012] Kernel Offset: 0x141ea00000 from 0xffffff8008000000
[ 5776.360026] CPU features: 0x0,2188200c
[ 5776.360035] Memory Limit: none
The test command run simulate_fw_crash firstly and it call into
ath10k_sdio_hif_stop from ath10k_core_restart, then napi_disable
is called and bit NAPI_STATE_SCHED is set. After that, function
ath10k_sdio_hif_stop is called again from ath10k_stop by command
"ifconfig wlan0 down" or "rmmod ath10k_sdio", then command blocked.
It is blocked by napi_synchronize, napi_disable will set bit with
NAPI_STATE_SCHED, and then napi_synchronize will enter dead loop
becuase bit NAPI_STATE_SCHED is set by napi_disable.
function of napi_synchronize
static inline void napi_synchronize(const struct napi_struct *n)
{
if (IS_ENABLED(CONFIG_SMP))
while (test_bit(NAPI_STATE_SCHED, &n->state))
msleep(1);
else
barrier();
}
function of napi_disable
void napi_disable(struct napi_struct *n)
{
might_sleep();
set_bit(NAPI_STATE_DISABLE, &n->state);
while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
msleep(1);
while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
msleep(1);
When it has more than one restart_work queued meanwhile, the 2nd
restart_work is very easy to break the 1st restart work and lead
recovery fail.
Add a flag to allow only one restart work running untill
device successfully recovered.
It already has flag ATH10K_FLAG_CRASH_FLUSH, but it can not use this
flag again, because it is clear in ath10k_core_start. The function
ieee80211_reconfig(called by ieee80211_restart_work) of mac80211 do
many things and drv_start(call to ath10k_core_start) is 1st thing,
when drv_start complete, it does not mean restart complete. So it
add new flag and clear it in ath10k_reconfig_complete, because it
is the last thing called from drv_reconfig_complete of function
ieee80211_reconfig, after it, the restart process finished.
The early_console_setup() function initializes sci_ports[0].port with an
object of type struct uart_port obtained from the struct earlycon_device
passed as an argument to early_console_setup().
Later, during serial port probing, the serial port used as earlycon
(e.g., port A) might be remapped to a different position in the sci_ports[]
array, and a different serial port (e.g., port B) might be assigned to slot
0. For example:
sci_ports[0] = port B
sci_ports[X] = port A
In this scenario, the new port mapped at index zero (port B) retains the
data associated with the earlycon configuration. Consequently, after the
Linux boot process, any access to the serial port now mapped to
sci_ports[0] (port B) will block the original earlycon port (port A).
To address this, introduce an early_console_exit() function to clean up
sci_ports[0] when earlycon is exited.
To prevent the cleanup of sci_ports[0] while the serial device is still
being used by earlycon, introduce the struct sci_port::probing flag and
account for it in early_console_exit().
Relocate the runtime PM enable operation to sci_probe_single(). This change
prepares the codebase for upcoming fixes.
While at it, replace the existing logic with a direct call to
devm_pm_runtime_enable() and remove sci_cleanup_single(). The
devm_pm_runtime_enable() function automatically handles disabling runtime
PM during driver removal.
On the Renesas RZ/G3S, when doing suspend to RAM, the uart_suspend_port()
is called. The uart_suspend_port() calls 3 times the
struct uart_port::ops::tx_empty() before shutting down the port.
According to the documentation, the struct uart_port::ops::tx_empty()
API tests whether the transmitter FIFO and shifter for the port is
empty.
The Renesas RZ/G3S SCIFA IP reports the number of data units stored in the
transmit FIFO through the FDR (FIFO Data Count Register). The data units
in the FIFOs are written in the shift register and transmitted from there.
The TEND bit in the Serial Status Register reports if the data was
transmitted from the shift register.
In the previous code, in the tx_empty() API implemented by the sh-sci
driver, it is considered that the TX is empty if the hardware reports the
TEND bit set and the number of data units in the FIFO is zero.
According to the HW manual, the TEND bit has the following meaning:
0: Transmission is in the waiting state or in progress.
1: Transmission is completed.
It has been noticed that when opening the serial device w/o using it and
then switch to a power saving mode, the tx_empty() call in the
uart_port_suspend() function fails, leading to the "Unable to drain
transmitter" message being printed on the console. This is because the
TEND=0 if nothing has been transmitted and the FIFOs are empty. As the
TEND=0 has double meaning (waiting state, in progress) we can't
determined the scenario described above.
Add a software workaround for this. This sets a variable if any data has
been sent on the serial console (when using PIO) or if the DMA callback has
been called (meaning something has been transmitted). In the tx_empty()
API the status of the DMA transaction is also checked and if it is
completed or in progress the code falls back in checking the hardware
registers instead of relying on the software variable.