Follow those steps:
# ip addr add 2001:123::1/32 dev eth0
# ip addr add 2001:123:456::2/64 dev eth0
# ip addr del 2001:123::1/32 dev eth0
# ip addr del 2001:123:456::2/64 dev eth0
and then prefix route of 2001:123::1/32 will still exist.
This is because ipv6_prefix_equal in check_cleanup_prefix_route
func does not check whether two IPv6 addresses have the same
prefix length. If the prefix of one address starts with another
shorter address prefix, even though their prefix lengths are
different, the return value of ipv6_prefix_equal is true.
Here I add a check of whether two addresses have the same prefix
to decide whether their prefixes are equal.
Fixes: 5b84efecb7d9 ("ipv6 addrconf: don't cleanup prefix route for IFA_F_NOPREFIXROUTE") Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com> Reported-by: Wenhao Zhang <zhangwenhao8@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
netif_rx() must be called under a strict contract.
At device dismantle phase, core networking clears IFF_UP
and flush_all_backlogs() is called after rcu grace period
to make sure no incoming packet might be in a cpu backlog
and still referencing the device.
Most drivers call netif_rx() from their interrupt handler,
and since the interrupts are disabled at device dismantle,
netif_rx() does not have to check dev->flags & IFF_UP
Virtual drivers do not have this guarantee, and must
therefore make the check themselves.
Otherwise we risk use-after-free and/or crashes.
Note this patch also fixes a small issue that came
with commit ce6502a8f957 ("vxlan: fix a use after free
in vxlan_encap_bypass"), since the dev->stats.rx_dropped
change was done on the wrong device.
Fixes: d342894c5d2f ("vxlan: virtual extensible lan") Fixes: ce6502a8f957 ("vxlan: fix a use after free in vxlan_encap_bypass") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Petr Machata <petrm@mellanox.com> Cc: Ido Schimmel <idosch@mellanox.com> Cc: Roopa Prabhu <roopa@cumulusnetworks.com> Cc: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The reason is that while event init code does several checks
for BTS events and prevents several unwanted config bits for
BTS event (like precise_ip), the PERF_EVENT_IOC_PERIOD allows
to create BTS event without those checks being done.
Following sequence will cause the crash:
If we create an 'almost' BTS event with precise_ip and callchains,
and it into a BTS event it will crash the perf_prepare_sample()
function because precise_ip events are expected to come
in with callchain data initialized, but that's not the
case for intel_pmu_drain_bts_buffer() caller.
Adding a check_period callback to be called before the period
is changed via PERF_EVENT_IOC_PERIOD. It will deny the change
if the event would become BTS. Plus adding also the limit_period
check as well.
Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20190204123532.GA4794@krava Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.16:
- Don't call limit_period operation, which doesn't exist and isn't needed here
- Add the intel_pmu_has_bts() function, which didn't previously exist here
- Adjust filenames, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix page fault handling code to fixup r16-r18 registers.
Before the patch code had off-by-two registers bug.
This bug caused overwriting of ps,pc,gp registers instead
of fixing intended r16,r17,r18 (see `struct pt_regs`).
More details:
Initially Dmitry noticed a kernel bug as a failure
on strace test suite. Test passes unmapped userspace
pointer to io_submit:
After a page fault `t0` should contain -EFALUT and `a1` is 0.
Instead `gp` was overwritten in place of `a1`.
This happens due to a off-by-two bug in `dpf_reg()` for `r16-r18`
(aka `a0-a2`).
I think the bug went unnoticed for a long time as `gp` is one
of scratch registers. Any kernel function call would re-calculate `gp`.
Dmitry tracked down the bug origin back to 2.1.32 kernel version
where trap_a{0,1,2} fields were inserted into struct pt_regs.
And even before that `dpf_reg()` contained off-by-one error.
Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: linux-alpha@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reported-and-reviewed-by: "Dmitry V. Levin" <ldv@altlinux.org>
Bug: https://bugs.gentoo.org/672040 Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Signed-off-by: Matt Turner <mattst88@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In the unlikely event that the kmalloc call in vmci_transport_socket_init()
fails, we end-up calling vmci_transport_destruct() with a NULL vmci_trans()
and oopsing.
This change addresses the above explicitly checking for zero vmci_trans()
at destruction time.
Reported-by: Xiumei Mu <xmu@redhat.com> Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Reviewed-by: Jorgen Hansen <jhansen@vmware.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Like Fujitsu CELSIUS H760, the H780 also has a three-button Elantech
touchpad, but the driver needs to be told so to enable the middle touchpad
button.
The elantech_dmi_force_crc_enabled quirk was not necessary with the H780.
Also document the fw_version and caps values detected for both H760 and
H780 models.
Signed-off-by: Matti Kurkela <Matti.Kurkela@iki.fi> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Just like Fujitsu CELSIUS H730, the H760 also has an Elantech touchpad with
the same quirks. Without this patch, the touchpad is useless out-of-the-box
as the mouse pointer won't move.
This patch makes the driver aware of both the crc_enabled=1 requirement and
the middle button, making the touchpad fully functional out-of-the-box.
Signed-off-by: Matti Kurkela <Matti.Kurkela@iki.fi> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The commit a60945fd08e4 ("ALSA: usb-audio: move implicit fb quirks to
separate function") introduced an error in the handling of quirks for
implicit feedback endpoints. This commit fixes this.
If a quirk successfully sets up an implicit feedback endpoint, usb-audio
no longer tries to find the implicit fb endpoint itself.
Fixes: a60945fd08e4 ("ALSA: usb-audio: move implicit fb quirks to separate function") Signed-off-by: Manuel Reinhardt <manuel.rhdt@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If we disabled IPv6 from the kernel command line (ipv6.disable=1), we should
not call ip6_err_gen_icmpv6_unreach(). This:
ip link add sit1 type sit local 192.0.2.1 remote 192.0.2.2 ttl 1
ip link set sit1 up
ip addr add 198.51.100.1/24 dev sit1
ping 198.51.100.2
if IPv6 is disabled at boot time, will crash the kernel.
v2: there's no need to use in6_dev_get(), use __in6_dev_get() instead,
as we only need to check that idev exists and we are under
rcu_read_lock() (from netif_receive_skb_internal()).
Reported-by: Jianlin Shi <jishi@redhat.com> Fixes: ca15a078bd90 ("sit: generate icmpv6 error when receiving icmpv4 error") Cc: Oussama Ghorbel <ghorbel@pivasoftware.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Recently syzkaller was able to create unkillablle processes by
creating a timer that is delivered as a thread local signal on SIGHUP,
and receiving SIGHUP SA_NODEFERER. Ultimately causing a loop failing
to deliver SIGHUP but always trying.
When the stack overflows delivery of SIGHUP fails and force_sigsegv is
called. Unfortunately because SIGSEGV is numerically higher than
SIGHUP next_signal tries again to deliver a SIGHUP.
From a quality of implementation standpoint attempting to deliver the
timer SIGHUP signal is wrong. We should attempt to deliver the
synchronous SIGSEGV signal we just forced.
We can make that happening in a fairly straight forward manner by
instead of just looking at the signal number we also look at the
si_code. In particular for exceptions (aka synchronous signals) the
si_code is always greater than 0.
That still has the potential to pick up a number of asynchronous
signals as in a few cases the same si_codes that are used
for synchronous signals are also used for asynchronous signals,
and SI_KERNEL is also included in the list of possible si_codes.
Still the heuristic is much better and timer signals are definitely
excluded. Which is enough to prevent all known ways for someone
sending a process signals fast enough to cause unexpected and
arguably incorrect behavior.
Fixes: a27341cd5fcb ("Prioritize synchronous signals over 'normal' signals") Tested-by: Dmitry Vyukov <dvyukov@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
[bwh: Backported to 3.16: s/kernel_siginfo_t/siginfo_t/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Recently syzkaller was able to create unkillablle processes by
creating a timer that is delivered as a thread local signal on SIGHUP,
and receiving SIGHUP SA_NODEFERER. Ultimately causing a loop
failing to deliver SIGHUP but always trying.
Upon examination it turns out part of the problem is actually most of
the solution. Since 2.5 signal delivery has found all fatal signals,
marked the signal group for death, and queued SIGKILL in every threads
thread queue relying on signal->group_exit_code to preserve the
information of which was the actual fatal signal.
The conversion of all fatal signals to SIGKILL results in the
synchronous signal heuristic in next_signal kicking in and preferring
SIGHUP to SIGKILL. Which is especially problematic as all
fatal signals have already been transformed into SIGKILL.
Instead of dequeueing signals and depending upon SIGKILL to
be the first signal dequeued, first test if the signal group
has already been marked for death. This guarantees that
nothing in the signal queue can prevent a process that needs
to exit from exiting.
Tested-by: Dmitry Vyukov <dvyukov@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com>
Ref: ebf5ebe31d2c ("[PATCH] signal-fixes-2.5.59-A4")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Now we can turn get_signal() to the main function.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
- Pass a ksignal struct to it
- Remove unused regs parameter
- Make it private as it's nowhere outside of kernel/signal.c is used
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
These parameters are nowhere used, so we can remove them.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
arch/unicore32/kernel/signal.c: In function ‘setup_frame’:
arch/unicore32/kernel/signal.c:257: error: ‘usig’ undeclared (first use in this function)
arch/unicore32/kernel/signal.c:279: error: ‘usig’ undeclared (first use in this function)
arch/unicore32/kernel/signal.c: In function ‘handle_signal’:
arch/unicore32/kernel/signal.c:306: warning: unused variable ‘tsk’
arch/unicore32/kernel/signal.c: In function ‘do_signal’:
arch/unicore32/kernel/signal.c:376: error: implicit declaration of function ‘get_signsl’
make[1]: *** [arch/unicore32/kernel/signal.o] Error 1
make: *** [arch/unicore32/kernel/signal.o] Error 2
Bisect points to commit 649671c90eaf ("unicore32: Use get_signal()
signal_setup_done()").
This code never even compiled. Reverting the patch does not work, since
previously used functions no longer exist, so try to fix it up. Compile
tested only.
Fixes: 649671c90eaf ("unicore32: Use get_signal() signal_setup_done()") Cc: Richard Weinberger <richard@nod.at> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Chris Metcalf <cmetcalf@tilera.com>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When a uprobe is installed on an instruction that we currently do not
emulate, we copy the instruction into a xol buffer and single step
that instruction. If that instruction generates a fault, we abort the
single stepping before invoking the signal handler. Once the signal
handler is done, the uprobe trap is hit again since the instruction is
retried and the process repeats.
We use uprobe_deny_signal() to detect if the xol instruction triggered
a signal. If so, we clear TIF_SIGPENDING and set TIF_UPROBE so that the
signal is not handled until after the single stepping is aborted. In
this case, uprobe_deny_signal() returns true and get_signal() ends up
returning 0. However, in do_signal(), we are not looking at the return
value, but depending on ksig.sig for further action, all with an
uninitialized ksig that is not touched in this scenario. Fix the same
by initializing ksig.sig to 0.
Fixes: 129b69df9c90 ("powerpc: Use get_signal() signal_setup_done()") Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
This inverts also the return codes of setup_*frame() to follow the
kernel convention.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
This inverts also the return codes of force_sigsegv_info()
and setup_frame() to follow the kernel convention.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Acked-by: Richard Kuo <rkuo@codeaurora.org> Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Tested-by: Mark Salter <msalter@redhat.com> Acked-by: Mark Salter <msalter@redhat.com> Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Steven Miao <realmz6@gmail.com>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.
Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Vineet Gupta <vgupta@synopsys.com>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
"signal: Always notice exiting tasks"
- Adjust to apply after "ARC: signal handling robustify"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We've received a bugreport that using LPM with a SAMSUNG
MZ7TE512HMHP-000L1 SSD leads to system instability, we already have
a quirk for the MZ7TD256HAFV-000L9, which is also a Samsun EVO 840 /
PM851 OEM model, so it seems some of these models have a LPM issue.
This commits adds a NOLPM quirk for the model string from the new
bugeport, to avoid the reported stability issues.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1571330 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Disable BCH soft reset according to MX23 erratum #2847 ("BCH soft
reset may cause bus master lock up") for MX28 too. It has the same
problem.
Observed problem: once per 100,000+ MX28 reboots NAND read failed on
DMA timeout errors:
[ 1.770823] UBI: attaching mtd3 to ubi0
[ 2.768088] gpmi_nand: DMA timeout, last DMA :1
[ 3.958087] gpmi_nand: BCH timeout, last DMA :1
[ 4.156033] gpmi_nand: Error in ECC-based read: -110
[ 4.161136] UBI warning: ubi_io_read: error -110 while reading 64
bytes from PEB 0:0, read only 0 bytes, retry
[ 4.171283] step 1 error
[ 4.173846] gpmi_nand: Chip: 0, Error -1
Without BCH soft reset we successfully executed 1,000,000 MX28 reboots.
I have a quote from NXP regarding this problem, from July 18th 2016:
"As the i.MX23 and i.MX28 are of the same generation, they share many
characteristics. Unfortunately, also the erratas may be shared.
In case of the documented erratas and the workarounds, you can also
apply the workaround solution of one device on the other one. This have
been reported, but I’m afraid that there are not an estimated date for
updating the Errata documents.
Please accept our apologies for any inconveniences this may cause."
Fixes: 6f2a6a52560a ("mtd: nand: gpmi: reset BCH earlier, too, to avoid NAND startup problems") Signed-off-by: Manfred Schlaegl <manfred.schlaegl@ginzinger.com> Signed-off-by: Martin Kepplinger <martin.kepplinger@ginzinger.com> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Reviewed-by: Fabio Estevam <festevam@gmail.com> Acked-by: Han Xu <han.xu@nxp.com> Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
[bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
It is normal user behaviour to start, stop, then start a stream
again without closing it. Currently this works for compressed
playback streams but not capture ones.
The states on a compressed capture stream go directly from OPEN to
PREPARED, unlike a playback stream which moves to SETUP and waits
for a write of data before moving to PREPARED. Currently however,
when a stop is sent the state is set to SETUP for both types of
streams. This leaves a capture stream in the situation where a new
start can't be sent as that requires the state to be PREPARED and
a new set_params can't be sent as that requires the state to be
OPEN. The only option being to close the stream, and then reopen.
Correct this issues by allowing snd_compr_drain_notify to set the
state depending on the stream direction, as we already do in
set_params.
Fixes: 49bb6402f1aa ("ALSA: compress_core: Add support for capture streams") Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Previously we set only the dma mask and not the coherent mask. Fix that.
Also, for clarity, make sure both are initially set to 64 bits.
Fixes: 0d00c488f3de: ("drm/vmwgfx: Fix the driver for large dma addresses") Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Deepak Rawat <drawat@vmware.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The function was unconditionally returning 0, and a caller would have to
rely on the returned fence pointer being NULL to detect errors. However,
the function vmw_execbuf_copy_fence_user() would expect a non-zero error
code in that case and would BUG otherwise.
So make sure we return a proper non-zero error code if the fence pointer
returned is NULL.
Fixes: ae2a104058e2: ("vmwgfx: Implement fence objects") Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Deepak Rawat <drawat@vmware.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The unbalance of master's promiscuity or allmulti will happen after ifdown
and ifup a slave interface which is in a bridge.
When we ifdown a slave interface , both the 'dsa_slave_close' and
'dsa_slave_change_rx_flags' will clear the master's flags. The flags
of master will be decrease twice.
In the other hand, if we ifup the slave interface again, since the
slave's flags were cleared the 'dsa_slave_open' won't set the master's
flag, only 'dsa_slave_change_rx_flags' that triggered by 'br_add_if'
will set the master's flags. The flags of master is increase once.
Only propagating flag changes when a slave interface is up makes
sure this does not happen. The 'vlan_dev_change_rx_flags' had the
same problem and was fixed, and changes here follows that fix.
Fixes: 91da11f870f0 ("net: Distributed Switch Architecture protocol support") Signed-off-by: Rundong Ge <rdong.ge@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Patch (b6c7a324df37b "MIPS: Fix get_frame_info() handling of
microMIPS function size.") introduces additional function size
check for microMIPS by only checking insn between ip and ip + func_size.
However, func_size in get_frame_info() is always 0 if KALLSYMS is not
enabled. This causes get_frame_info() to return immediately without
calculating correct frame_size, which in turn causes "Can't analyze
schedule() prologue" warning messages at boot time.
This patch removes func_size check, and let the frame_size check run
up to 128 insns for both MIPS and microMIPS.
Signed-off-by: Jun-Ru Chang <jrjang@realtek.com> Signed-off-by: Tony Wu <tonywu@realtek.com> Signed-off-by: Paul Burton <paul.burton@mips.com> Fixes: b6c7a324df37b ("MIPS: Fix get_frame_info() handling of microMIPS function size.") Cc: <ralf@linux-mips.org> Cc: <jhogan@kernel.org> Cc: <macro@mips.com> Cc: <yamada.masahiro@socionext.com> Cc: <peterz@infradead.org> Cc: <mingo@kernel.org> Cc: <linux-mips@vger.kernel.org> Cc: <linux-kernel@vger.kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Work for Bridgeport events is currently placed on a driver-wide
workqueue. If the card is removed and freed while any such work is still
active, this causes a use-after-free.
So put the events on a per-card queue, where we can control their
lifetime. As we also don't want stale events to last beyond an
offline & online cycle, flush this queue when setting the card offline.
Fixes: b4d72c08b358 ("qeth: bridgeport support - basic control") Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16:
- Add gdev parameter to qeth_alloc_card(), as done upstream by commit 121ca39aa558 "s390/qeth: uninstall IRQ handler on device removal"
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
A card's close_dev work is scheduled on a driver-wide workqueue. If the
card is removed and freed while the work is still active, this causes a
use-after-free.
So make sure that the work is completed before freeing the card.
Fixes: 0f54761d167f ("qeth: Support VEPA mode") Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The error path in qeth_alloc_qdio_buffers() that takes care of
cleaning up the Output Queues is buggy. It first frees the queue, but
then calls qeth_clear_outq_buffers() with that very queue struct.
Make the call to qeth_clear_outq_buffers() part of the free action
(in the correct order), and while at it fix the naming of the helper.
Fixes: 0da9581ddb0f ("qeth: exploit asynchronous delivery of storage blocks") Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16:
- Add the qeth_free_output_queue() function, which didn't exist here
- Keep using kfree() to free to free the qeth_qdio_out_q structure] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
reveals the character arrays prev_comm and next_comm are per
default unsigned char and have values in the range of 0..255.
On x86 both fields are signed as this output shows:
[root@f29]# cat /sys/kernel/debug/tracing/events/sched/sched_switch/format
name: sched_switch
ID: 287
format:
field:unsigned short common_type; offset:0; size:2; signed:0;
...
field:char prev_comm[16]; offset:8; size:16; signed:1;
...
field:char next_comm[16]; offset:40; size:16; signed:1;
and the character arrays prev_comm and next_comm are per default signed
char and have values in the range of -1..127. The implementation of
type char is architecture specific.
Since the character arrays in both tracepoints sched_switch and
sched_wakeup should contain ascii characters, simply omit the check for
signedness in the test case.
Output before:
[root@m35lp76 perf]# ./perf test -F 14
14: Parse sched tracepoints fields :
--- start ---
sched:sched_switch: "prev_comm" signedness(0) is wrong, should be 1
sched:sched_switch: "next_comm" signedness(0) is wrong, should be 1
sched:sched_wakeup: "comm" signedness(0) is wrong, should be 1
---- end ----
14: Parse sched tracepoints fields : FAILED!
[root@m35lp76 perf]#
Output after:
[root@m35lp76 perf]# ./perf test -Fv 14
14: Parse sched tracepoints fields :
--- start ---
---- end ----
Parse sched tracepoints fields: Ok
[root@m35lp76 perf]#
Fixes: 489338a717a0 ("perf tests evsel-tp-sched: Fix bitwise operator") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Link: http://lkml.kernel.org/r/20190219153639.31267-1-tmricht@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Notice that the use of the bitwise OR operator '|' always leads to true
in this particular case, which seems a bit suspicious due to the context
in which this expression is being used.
Fix this by using bitwise AND operator '&' instead.
This bug was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Fixes: 6a6cd11d4e57 ("perf test: Add test for the sched tracepoint format fields") Link: http://lkml.kernel.org/r/20190122233439.GA5868@embeddedor Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 4076e755dbec ("dmatest: convert to dmaengine_unmap_data") Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
After the DMA transfer is done, we don't need to call the un-mapping code
in 3 places. One is enough.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>
[bwh: Backported to 3.16 as dependency of commit 6454368a804c
"dmaengine: dmatest: Abort test in case of mapping error"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The perf tool uses /proc/sys/kernel/perf_event_mlock_kb to determine how
large its ringbuffer mmap should be. This can be configured to arbitrary
values, which can be larger than the maximum possible allocation from
kmalloc.
When this is configured to a suitably large value (e.g. thanks to the
perf fuzzer), attempting to use perf record triggers a WARN_ON_ONCE() in
__alloc_pages_nodemask():
WARNING: CPU: 2 PID: 5666 at mm/page_alloc.c:4511 __alloc_pages_nodemask+0x3f8/0xbc8
Let's avoid this by checking that the requested allocation is possible
before calling kzalloc.
Reported-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20190110142745.25495-1-mark.rutland@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Some PCI uncore PMUs cannot be registered on an 8-socket system (HPE
Superdome Flex).
To understand which Socket the PCI uncore PMUs belongs to, perf retrieves
the local Node ID of the uncore device from CPUNODEID(0xC0) of the PCI
configuration space, and the mapping between Socket ID and Node ID from
GIDNIDMAP(0xD4). The Socket ID can be calculated accordingly.
The local Node ID is only available at bit 2:0, but current code doesn't
mask it. If a BIOS doesn't clear the rest of the bits, an incorrect Node ID
will be fetched.
Filter the Node ID by adding a mask.
Reported-by: Song Liu <songliubraving@fb.com> Tested-by: Song Liu <songliubraving@fb.com> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 7c94ee2e0917 ("perf/x86: Add Intel Nehalem and Sandy Bridge-EP uncore support") Link: https://lkml.kernel.org/r/1548600794-33162-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
There are multiple issues with bcm2835_dma_abort() (which is called on
termination of a transaction):
* The algorithm to abort the transaction first pauses the channel by
clearing the ACTIVE flag in the CS register, then waits for the PAUSED
flag to clear. Page 49 of the spec documents the latter as follows:
"Indicates if the DMA is currently paused and not transferring data.
This will occur if the active bit has been cleared [...]"
https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf
So the function is entering an infinite loop because it is waiting for
PAUSED to clear which is always set due to the function having cleared
the ACTIVE flag. The only thing that's saving it from itself is the
upper bound of 10000 loop iterations.
The code comment says that the intention is to "wait for any current
AXI transfer to complete", so the author probably wanted to check the
WAITING_FOR_OUTSTANDING_WRITES flag instead. Amend the function
accordingly.
* The CS register is only read at the beginning of the function. It
needs to be read again after pausing the channel and before checking
for outstanding writes, otherwise writes which were issued between
the register read at the beginning of the function and pausing the
channel may not be waited for.
* The function seeks to abort the transfer by writing 0 to the NEXTCONBK
register and setting the ABORT and ACTIVE flags. Thereby, the 0 in
NEXTCONBK is sought to be loaded into the CONBLK_AD register. However
experimentation has shown this approach to not work: The CONBLK_AD
register remains the same as before and the CS register contains
0x00000030 (PAUSED | DREQ_STOPS_DMA). In other words, the control
block is not aborted but merely paused and it will be resumed once the
next DMA transaction is started. That is absolutely not the desired
behavior.
A simpler approach is to set the channel's RESET flag instead. This
reliably zeroes the NEXTCONBK as well as the CS register. It requires
less code and only a single MMIO write. This is also what popular
user space DMA drivers do, e.g.:
https://github.com/metachris/RPIO/blob/master/source/c_pwm/pwm.c
Note that the spec is contradictory whether the NEXTCONBK register
is writeable at all. On the one hand, page 41 claims:
"The value loaded into the NEXTCONBK register can be overwritten so
that the linked list of Control Block data structures can be
dynamically altered. However it is only safe to do this when the DMA
is paused."
On the other hand, page 40 specifies:
"Only three registers in each channel's register set are directly
writeable (CS, CONBLK_AD and DEBUG). The other registers (TI,
SOURCE_AD, DEST_AD, TXFR_LEN, STRIDE & NEXTCONBK), are automatically
loaded from a Control Block data structure held in external memory."
Fixes: 96286b576690 ("dmaengine: Add support for BCM2835") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: Frank Pavlic <f.pavlic@kunbus.de> Cc: Martin Sperl <kernel@martin.sperl.org> Cc: Florian Meier <florian.meier@koalo.de> Cc: Clive Messer <clive.m.messer@gmail.com> Cc: Matthias Reichl <hias@horus.com> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Acked-by: Florian Kauer <florian.kauer@koalo.de> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If IRQ handlers are threaded (either because CONFIG_PREEMPT_RT_BASE is
enabled or "threadirqs" was passed on the command line) and if system
load is sufficiently high that wakeup latency of IRQ threads degrades,
SPI DMA transactions on the BCM2835 occasionally break like this:
ks8851 spi0.0: SPI transfer timed out
bcm2835-dma 3f007000.dma: DMA transfer could not be terminated
ks8851 spi0.0 eth2: ks8851_rdfifo: spi_sync() failed
The root cause is an assumption made by the DMA driver which is
documented in a code comment in bcm2835_dma_terminate_all():
/*
* Stop DMA activity: we assume the callback will not be called
* after bcm_dma_abort() returns (even if it does, it will see
* c->desc is NULL and exit.)
*/
That assumption falls apart if the IRQ handler bcm2835_dma_callback() is
threaded: A client may terminate a descriptor and issue a new one
before the IRQ handler had a chance to run. In fact the IRQ handler may
miss an *arbitrary* number of descriptors. The result is the following
race condition:
1. A descriptor finishes, its interrupt is deferred to the IRQ thread.
2. A client calls dma_terminate_async() which sets channel->desc = NULL.
3. The client issues a new descriptor. Because channel->desc is NULL,
bcm2835_dma_issue_pending() immediately starts the descriptor.
4. Finally the IRQ thread runs and writes BCM2835_DMA_INT to the CS
register to acknowledge the interrupt. This clears the ACTIVE flag,
so the newly issued descriptor is paused in the middle of the
transaction. Because channel->desc is not NULL, the IRQ thread
finalizes the descriptor and tries to start the next one.
I see two possible solutions: The first is to call synchronize_irq()
in bcm2835_dma_issue_pending() to wait until the IRQ thread has
finished before issuing a new descriptor. The downside of this approach
is unnecessary latency if clients desire rapidly terminating and
re-issuing descriptors and don't have any use for an IRQ callback.
(The SPI TX DMA channel is a case in point.)
A better alternative is to make the IRQ thread recognize that it has
missed descriptors and avoid finalizing the newly issued descriptor.
So first of all, set the ACTIVE flag when acknowledging the interrupt.
This keeps a newly issued descriptor running.
If the descriptor was finished, the channel remains idle despite the
ACTIVE flag being set. However the ACTIVE flag can then no longer be
used to check whether the channel is idle, so instead check whether
the register containing the current control block address is zero
and finalize the current descriptor only if so.
That way, there is no impact on latency and throughput if the client
doesn't care for the interrupt: Only minimal additional overhead is
introduced for non-cyclic descriptors as one further MMIO read is
necessary per interrupt to check for idleness of the channel. Cyclic
descriptors are sped up slightly by removing one MMIO write per
interrupt.
Fixes: 96286b576690 ("dmaengine: Add support for BCM2835") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: Frank Pavlic <f.pavlic@kunbus.de> Cc: Martin Sperl <kernel@martin.sperl.org> Cc: Florian Meier <florian.meier@koalo.de> Cc: Clive Messer <clive.m.messer@gmail.com> Cc: Matthias Reichl <hias@horus.com> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Acked-by: Florian Kauer <florian.kauer@koalo.de> Signed-off-by: Vinod Koul <vkoul@kernel.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Add additional defines describing the DMA registers
as well as adding some more documentation to those registers.
Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Eric Anholt <eric@anholt.net> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
[bwh: Backported to 3.16 as dependency of commit 9e528c799d17
"dmaengine: bcm2835: Fix abort of transactions"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Once the "ld_queue" list is not empty, next descriptor will migrate
into "ld_active" list. The "desc" variable will be overwritten
during that transition. And later the dmaengine_desc_get_callback_invoke()
will use it as an argument. As result we invoke wrong callback.
That behaviour was in place since:
commit fcaaba6c7136 ("dmaengine: imx-dma: fix callback path in tasklet").
But after commit 4cd13c21b207 ("softirq: Let ksoftirqd do its job")
things got worse, since possible delay between tasklet_schedule()
from DMA irq handler and actual tasklet function execution got bigger.
And that gave more time for new DMA request to be submitted and
to be put into "ld_queue" list.
It has been noticed that DMA issue is causing problems for "mxc-mmc"
driver. While stressing the system with heavy network traffic and
writing/reading to/from sd card simultaneously the timeout may happen:
10013000.sdhci: mxcmci_watchdog: read time out (status = 0x30004900)
That often lead to file system corruption.
Signed-off-by: Leonid Iziumtsev <leonid.iziumtsev@gmail.com> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We had a race in the old balloon compaction code before b1123ea6d3b3
("mm: balloon: use general non-lru movable page feature") refactored it
that became visible after backporting 195a8c43e93d ("virtio-balloon:
deflate via a page list") without the refactoring.
The bug existed from commit d6d86c0a7f8d ("mm/balloon_compaction:
redesign ballooned pages management") till b1123ea6d3b3 ("mm: balloon:
use general non-lru movable page feature"). d6d86c0a7f8d
("mm/balloon_compaction: redesign ballooned pages management") was
backported to 3.12, so the broken kernels are stable kernels [3.12 -
4.7].
There was a subtle race between dropping the page lock of the newpage in
__unmap_and_move() and checking for __is_movable_balloon_page(newpage).
Just after dropping this page lock, virtio-balloon could go ahead and
deflate the newpage, effectively dequeueing it and clearing PageBalloon,
in turn making __is_movable_balloon_page(newpage) fail.
This resulted in dropping the reference of the newpage via
putback_lru_page(newpage) instead of put_page(newpage), leading to
page->lru getting modified and a !LRU page ending up in the LRU lists.
With 195a8c43e93d ("virtio-balloon: deflate via a page list")
backported, one would suddenly get corrupted lists in
release_pages_balloon():
- WARNING: CPU: 13 PID: 6586 at lib/list_debug.c:59 __list_del_entry+0xa1/0xd0
- list_del corruption. prev->next should be ffffe253961090a0, but was dead000000000100
Nowadays this race is no longer possible, but it is hidden behind very
ugly handling of __ClearPageMovable() and __PageMovable().
__ClearPageMovable() will not make __PageMovable() fail, only
PageMovable(). So the new check (__PageMovable(newpage)) will still
hold even after newpage was dequeued by virtio-balloon.
If anybody would ever change that special handling, the BUG would be
introduced again. So instead, make it explicit and use the information
of the original isolated page before migration.
This patch can be backported fairly easy to stable kernels (in contrast
to the refactoring).
Link: http://lkml.kernel.org/r/20190129233217.10747-1-david@redhat.com Fixes: d6d86c0a7f8d ("mm/balloon_compaction: redesign ballooned pages management") Signed-off-by: David Hildenbrand <david@redhat.com> Reported-by: Vratislav Bendel <vbendel@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Rafael Aquini <aquini@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Jan Kara <jack@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Vratislav Bendel <vbendel@redhat.com> Cc: Rafael Aquini <aquini@redhat.com> Cc: Konstantin Khlebnikov <k.khlebnikov@samsung.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.16:
- Add the is_lru flag variable to unmap_and_move()
- Keep using __is_movable_balloon_page() instead of __PageMovable()
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Currently memory_failure() is racy against process's exiting, which
results in kernel crash by null pointer dereference.
The root cause is that memory_failure() uses force_sig() to forcibly
kill asynchronous (meaning not in the current context) processes. As
discussed in thread https://lkml.org/lkml/2010/6/8/236 years ago for OOM
fixes, this is not a right thing to do. OOM solves this issue by using
do_send_sig_info() as done in commit d2d393099de2 ("signal:
oom_kill_task: use SEND_SIG_FORCED instead of force_sig()"), so this
patch is suggesting to do the same for hwpoison. do_send_sig_info()
properly accesses to siglock with lock_task_sighand(), so is free from
the reported race.
I confirmed that the reported bug reproduces with inserting some delay
in kill_procs(), and it never reproduces with this patch.
Note that memory_failure() can send another type of signal using
force_sig_mceerr(), and the reported race shouldn't happen on it because
force_sig_mceerr() is called only for synchronous processes (i.e.
BUS_MCEERR_AR happens only when some process accesses to the corrupted
memory.)
Link: http://lkml.kernel.org/r/20190116093046.GA29835@hori1.linux.bs1.fc.nec.co.jp Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reported-by: Jane Chu <jane.chu@oracle.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Syzbot instance running on upstream kernel found a use-after-free bug in
oom_kill_process. On further inspection it seems like the process
selected to be oom-killed has exited even before reaching
read_lock(&tasklist_lock) in oom_kill_process(). More specifically the
tsk->usage is 1 which is due to get_task_struct() in oom_evaluate_task()
and the put_task_struct within for_each_thread() frees the tsk and
for_each_thread() tries to access the tsk. The easiest fix is to do
get/put across the for_each_thread() on the selected task.
Now the next question is should we continue with the oom-kill as the
previously selected task has exited? However before adding more
complexity and heuristics, let's answer why we even look at the children
of oom-kill selected task? The select_bad_process() has already selected
the worst process in the system/memcg. Due to race, the selected
process might not be the worst at the kill time but does that matter?
The userspace can use the oom_score_adj interface to prefer children to
be killed before the parent. I looked at the history but it seems like
this is there before git history.
Link: http://lkml.kernel.org/r/20190121215850.221745-1-shakeelb@google.com Reported-by: syzbot+7fbbfa368521945f0e3d@syzkaller.appspotmail.com Fixes: 6b0c81b3be11 ("mm, oom: reduce dependency on tasklist_lock") Signed-off-by: Shakeel Butt <shakeelb@google.com> Reviewed-by: Roman Gushchin <guro@fb.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The "p" buffer is 0x4000 bytes long. B3_RI_WTO_R1 is 0x190. The value
of "regs->len" is in the 1-0x4000 range. The bug here is that
"regs->len - B3_RI_WTO_R1" can be a negative value which would lead to
memory corruption and an abrupt crash.
Fixes: c3f8be961808 ("[PATCH] skge: expand ethtool debug register dump") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Some drivers use IEEE80211_KEY_FLAG_SW_MGMT_TX to indicate that management
frames need to be software encrypted. Since normal data packets are still
encrypted by the hardware, crypto_tx_tailroom_needed_cnt gets decremented
after key upload to hw. This can lead to passing skbs to ccmp_encrypt_skb,
which don't have the necessary tailroom for software encryption.
Change the code to add tailroom for encrypted management packets, even if
crypto_tx_tailroom_needed_cnt is 0.
Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[bwh: Backported to 3.16: we always expand cloned skbs here; don't change that] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The size of L2TPv2 header with all optional fields is 14 bytes.
l2tp_udp_recv_core only moves 10 bytes to the linear part of a
skb. This may lead to l2tp_recv_common read data outside of a skb.
This patch make sure that there is at least 14 bytes in the linear
part of a skb to meet the maximum need of l2tp_udp_recv_core and
l2tp_recv_common. The minimum size of both PPP HDLC-like frame and
Ethernet frame is larger than 14 bytes, so we are safe to do so.
Also remove L2TP_HDR_SIZE_NOSEQ, it is unused now.
Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Suggested-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Jacob Wen <jian.w.wen@oracle.com> Acked-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The nr_dentry_unused per-cpu counter tracks dentries in both the LRU
lists and the shrink lists where the DCACHE_LRU_LIST bit is set.
The shrink_dcache_sb() function moves dentries from the LRU list to a
shrink list and subtracts the dentry count from nr_dentry_unused. This
is incorrect as the nr_dentry_unused count will also be decremented in
shrink_dentry_list() via d_shrink_del().
To fix this double decrement, the decrement in the shrink_dcache_sb()
function is taken out.
Fixes: 4e717f5c1083 ("list_lru: remove special case function list_lru_dispose_all." Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Handling short packets (length < max packet size) in the Inventra DMA
engine in the MUSB driver causes the MUSB DMA controller to hang. An
example of a problem that is caused by this problem is when streaming
video out of a UVC gadget, only the first video frame is transferred.
For short packets (mode-0 or mode-1 DMA), MUSB_TXCSR_TXPKTRDY must be
set manually by the driver. This was previously done in musb_g_tx
(musb_gadget.c), but incorrectly (all csr flags were cleared, and only
MUSB_TXCSR_MODE and MUSB_TXCSR_TXPKTRDY were set). Fixing that problem
allows some requests to be transferred correctly, but multiple requests
were often put together in one USB packet, and caused problems if the
packet size was not a multiple of 4. Instead, set MUSB_TXCSR_TXPKTRDY
in dma_controller_irq (musbhsdma.c), just like host mode transfers.
This topic was originally tackled by Nicolas Boichat [0] [1] and is
discussed further at [2] as part of his GSoC project [3].
Booting 4.20 on a TheCUS N2100 results in a kernel oops while probing
PCI, due to n2100_pci_map_irq() having been discarded during boot.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When doing reads beyound the end of a file the server returns
error STATUS_END_OF_FILE error which is mapped to -ENODATA.
Currently we report it as a failure which confuses read stats.
Change it to not consider -ENODATA as failure for stat purposes.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Don't set octeon_dma_bar_type if PCI is disabled. This avoids creation
of the MSI irqchip later on, and saves a bit of memory.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Signed-off-by: Paul Burton <paul.burton@mips.com> Fixes: a214720cbf50 ("Disable MSI also when pcie-octeon.pcie_disable on") Cc: linux-mips@vger.kernel.org Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
There are two issues here. First if cmgr->hba is not set early enough then
it leads to a NULL dereference. Second if we don't completely initialize
cmgr->io_bdt_pool[] then we end up dereferencing uninitialized pointers.
Fixes: 853e2bd2103a ("[SCSI] bnx2fc: Broadcom FCoE offload driver") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
[bwh: Backorted to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The patch 52898025cf7d: "[S390] dasd: security and PSF update patch
for EMC CKD ioctl" from Mar 8, 2010, leads to the following static
checker warning:
drivers/s390/block/dasd_eckd.c:4486 dasd_symm_io()
error: using offset into zero size array 'psf_data[]'
drivers/s390/block/dasd_eckd.c
4458 /* Copy parms from caller */
4459 rc = -EFAULT;
4460 if (copy_from_user(&usrparm, argp, sizeof(usrparm)))
^^^^^^^
The user can specify any "usrparm.psf_data_len". They choose zero by
mistake.
4461 goto out;
4462 if (is_compat_task()) {
4463 /* Make sure pointers are sane even on 31 bit. */
4464 rc = -EINVAL;
4465 if ((usrparm.psf_data >> 32) != 0)
4466 goto out;
4467 if ((usrparm.rssd_result >> 32) != 0)
4468 goto out;
4469 usrparm.psf_data &= 0x7fffffffULL;
4470 usrparm.rssd_result &= 0x7fffffffULL;
4471 }
4472 /* alloc I/O data area */
4473 psf_data = kzalloc(usrparm.psf_data_len, GFP_KERNEL
| GFP_DMA);
4474 rssd_result = kzalloc(usrparm.rssd_result_len, GFP_KERNEL
| GFP_DMA);
4475 if (!psf_data || !rssd_result) {
kzalloc() returns a ZERO_SIZE_PTR (0x16).
4476 rc = -ENOMEM;
4477 goto out_free;
4478 }
4479
4480 /* get syscall header from user space */
4481 rc = -EFAULT;
4482 if (copy_from_user(psf_data,
4483 (void __user *)(unsigned long)
usrparm.psf_data,
4484 usrparm.psf_data_len))
But now we're assuming that "->psf_data_len" was at least 2 bytes.
Fix this by checking the user specified length psf_data_len.
Fixes: 52898025cf7d ("[S390] dasd: security and PSF update patch for EMC CKD ioctl") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Stefan Haberland <sth@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
power off the phy should be done before populate the phy. Otherwise,
am335x_init() could be called by the phy owner to power on the phy first,
then am335x_phy_probe() turns off the phy again without the caller knowing
it.
Fixes: 2fc711d76352 ("usb: phy: am335x: Enable USB remote wakeup using PHY wakeup") Signed-off-by: Bin Liu <b-liu@ti.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix bitwise and boolean operations by enclosing the expression:
intcsr & (1 << NET2272_PCI_IRQ)
in parentheses, before applying the boolean operator '!'.
Notice that this code has been there since 2011. So, it would
be helpful if someone can double-check this.
This issue was detected with the help of Coccinelle.
Fixes: ceb80363b2ec ("USB: net2272: driver for PLX NET2272 USB device controller") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
[bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The buggy address belongs to the object at ffff88034c30bcc8
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 8 bytes inside of
512-byte region [ffff88034c30bcc8, ffff88034c30bec8)
The buggy address belongs to the page:
The following race between change mode and xmit flow is the reason for
this use-after-free:
Change mode Send packet 1 to GID XX Send packet 2 to GID XX
| | |
start | |
| | |
| | |
| Create new path for GID XX |
| and update neigh path |
| | |
| | |
| | |
flush_paths | |
| |
queue_work(cm.start_task) |
| Path for GID XX not found
| create new path
|
|
start_task runs with old
released path
There is no locking to protect the lifetime of the path through the
ipoib_cm_tx struct, so delete it entirely and always use the newly looked
up path under the priv->lock.
Fixes: 546481c2816e ("IB/ipoib: Fix memory corruption in ipoib cm mode connect flow") Signed-off-by: Feras Daoud <ferasda@mellanox.com> Reviewed-by: Erez Shitrit <erezsh@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The single-step debugging of KVM guests on x86 is broken: if we run
gdb 'stepi' command at the breakpoint when the guest interrupts are
enabled, RIP always jumps to native_apic_mem_write(). Then other
nasty effects follow.
Long investigation showed that on Jun 7, 2017 the
commit c8401dda2f0a00cd25c0 ("KVM: x86: fix singlestepping over syscall")
introduced the kvm_run.debug corruption: kvm_vcpu_do_singlestep() can
be called without X86_EFLAGS_TF set.
Let's fix it. Please consider that for -stable.
Signed-off-by: Alexander Popov <alex.popov@linux.com> Fixes: c8401dda2f0a00cd25c0 ("KVM: x86: fix singlestepping over syscall") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
debugfs_rename() needs to check that the dentries passed into it really
are valid, as sometimes they are not (i.e. if the return value of
another debugfs call is passed into this one.) So fix this up by
properly checking if the two parent directories are errors (they are
allowed to be NULL), and if the dentry to rename is not NULL or an
error.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Driver reads the query HCA capabilities without the corresponding masks.
Without the correct masks, the base addresses of the queues are
unaligned. In addition some reserved bits were wrongly read. Using the
correct masks, ensures alignment of the base addresses and allows future
firmware versions safe use of the reserved bits.
Fixes: ab9c17a009ee ("mlx4_core: Modify driver initialization flow to accommodate SRIOV for Ethernet") Fixes: 0ff1fb654bec ("{NET, IB}/mlx4: Add device managed flow steering firmware API") Signed-off-by: Aya Levin <ayal@mellanox.com> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16:
- There are no num_sys_eqs or dmfs_high_steer_mode parameters
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When a VM is terminated, the VFIO driver detaches all pass-through
devices from VFIO domain by clearing domain id and page table root
pointer from each device table entry (DTE), and then invalidates
the DTE. Then, the VFIO driver unmap pages and invalidate IOMMU pages.
Currently, the IOMMU driver keeps track of which IOMMU and how many
devices are attached to the domain. When invalidate IOMMU pages,
the driver checks if the IOMMU is still attached to the domain before
issuing the invalidate page command.
However, since VFIO has already detached all devices from the domain,
the subsequent INVALIDATE_IOMMU_PAGES commands are being skipped as
there is no IOMMU attached to the domain. This results in data
corruption and could cause the PCI device to end up in indeterministic
state.
Fix this by invalidate IOMMU pages when detach a device, and
before decrementing the per-domain device reference counts.
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Suggested-by: Joerg Roedel <joro@8bytes.org> Co-developed-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Fixes: 6de8ad9b9ee0 ('x86/amd-iommu: Make iommu_flush_pages aware of multiple IOMMUs') Signed-off-by: Joerg Roedel <jroedel@suse.de>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Tina Zhang <tina.zhang@intel.com> Cc: Adam Jackson <ajax@redhat.com> Cc: Dave Airlie <airlied@redhat.com> Cc: Daniel Vetter <daniel@ffwll.ch>
[danvet: Add additional explanations + cc: stable.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/1548228539-3061-1-git-send-email-tina.zhang@intel.com Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix this by sanitizing channel and addr->channel before using them to
index user->intf->addrinfo and intf->addrinfo, correspondingly.
Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Corey Minyard <cminyard@mvista.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Kyungtae Kim detected a potential integer overflow in bcm_[rx|tx]_setup()
when the conversion into ktime multiplies the given value with NSEC_PER_USEC
(1000).
Add a check for the given tv_usec, so that the value stays below one second.
Additionally limit the tv_sec value to a reasonable value for CAN related
use-cases of 400 days and ensure all values to be positive.
Reported-by: Kyungtae Kim <kt0755@gmail.com> Tested-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Tested-by: Kyungtae Kim <kt0755@gmail.com> Acked-by: Andre Naujoks <nautsch2@gmail.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This patch revert commit 7da11ba5c506
("can: dev: __can_get_echo_skb(): print error message, if trying to echo non existing skb")
After introduction of this change we encountered following new error
message on various i.MX plattforms (flexcan):
| flexcan 53fc8000.can can0: __can_get_echo_skb: BUG! Trying to echo non
| existing skb: can_priv::echo_skb[0]
The introduction of the message was a mistake because
priv->echo_skb[idx] = NULL is a perfectly valid in following case: If
CAN_RAW_LOOPBACK is disabled (setsockopt) in applications, the pkt_type
of the tx skb's given to can_put_echo_skb is set to PACKET_LOOPBACK. In
this case can_put_echo_skb will not set priv->echo_skb[idx]. It is
therefore kept NULL.
As additional argument for revert: The order of check and usage of idx
was changed. idx is used to access an array element before checking it's
boundaries.
Signed-off-by: Manfred Schlaegl <manfred.schlaegl@ginzinger.com> Fixes: 7da11ba5c506 ("can: dev: __can_get_echo_skb(): print error message, if trying to echo non existing skb") Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Some tty line disciplines do not have a receive buf callback, so
properly check for that before calling it. If they do not have this
callback, just eat the character quietly, as we can't fail this call.
Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix this by sanitizing ipcnum before using it to index pDrvData->IPCs.
Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix __might_sleep warning[1] in tty/n_hdlc.c read due to copy_to_user
call while current is TASK_INTERRUPTIBLE. This is a false positive
since the code path does not depend on current state remaining
TASK_INTERRUPTIBLE. The loop breaks out and sets TASK_RUNNING after
calling copy_to_user.
This patch supresses the warning by setting TASK_RUNNING before calling
copy_to_user.
We were experiencing a crash similar to the one reported as part of
commit:a5ba1d95e46e ("uart: fix race between uart_put_char() and
uart_shutdown()") in our testbed as well. We continue to observe the same
crash after integrating the commit a5ba1d95e46e ("uart: fix race between
uart_put_char() and uart_shutdown()")
On reviewing the change, the port lock should be taken prior to checking for
if (!circ->buf) in fn. __uart_put_char and other fns. that update the buffer
uart_state->xmit.
Traceback:
[11/27/2018 06:24:32.4870] Unable to handle kernel NULL pointer dereference
at virtual address 0000003b
The skb header should be set to ethernet header before using
is_skb_forwardable. Because the ethernet header length has been
considered in is_skb_forwardable(including dev->hard_header_len
length).
To reproduce the issue:
1, add 2 ports on linux bridge br using following commands:
$ brctl addbr br
$ brctl addif br eth0
$ brctl addif br eth1
2, the MTU of eth0 and eth1 is 1500
3, send a packet(Data 1480, UDP 8, IP 20, Ethernet 14, VLAN 4)
from eth0 to eth1
So the expect result is packet larger than 1500 cannot pass through
eth0 and eth1. But currently, the packet passes through success, it
means eth1's MTU limit doesn't take effect.
Fixes: f6367b4660dd ("bridge: use is_skb_forwardable in forward path") Cc: bridge@lists.linux-foundation.org Cc: Nkolay Aleksandrov <nikolay@cumulusnetworks.com> Cc: Roopa Prabhu <roopa@cumulusnetworks.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16:
- br_dev_queue_push_xmit() has to call nf_bridge_maybe_copy_header()
before pushing the Ethernet header
- adjust context, indentation] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
do_page_fault() forgot to relinquish mmap_sem if a signal came while
handling handle_mm_fault() - due to say a ctl+c or oom etc.
This would later cause a deadlock by acquiring it twice.
This came to light when running libc testsuite tst-tls3-malloc test but
is likely also the cause for prior seen LTP failures. Using lockdep
clearly showed what the issue was.
| # while true; do ./tst-tls3-malloc ; done
| Didn't expect signal from child: got `Segmentation fault'
| ^C
| ============================================
| WARNING: possible recursive locking detected
| 4.17.0+ #25 Not tainted
| --------------------------------------------
| tst-tls3-malloc/510 is trying to acquire lock:
| 606c7728 (&mm->mmap_sem){++++}, at: __might_fault+0x28/0x5c
|
|but task is already holding lock:
|606c7728 (&mm->mmap_sem){++++}, at: do_page_fault+0x9c/0x2a0
|
| other info that might help us debug this:
| Possible unsafe locking scenario:
|
| CPU0
| ----
| lock(&mm->mmap_sem);
| lock(&mm->mmap_sem);
|
| *** DEADLOCK ***
|
------------------------------------------------------------
What the change does is not obvious (note to myself)
prior code was
| do_page_fault
|
| down_read() <-- lock taken
| handle_mm_fault <-- signal pending as this runs
| if fatal_signal_pending
| if VM_FAULT_ERROR
| up_read
| if user_mode
| return <-- lock still held, this was the BUG
New code
| do_page_fault
|
| down_read() <-- lock taken
| handle_mm_fault <-- signal pending as this runs
| if fatal_signal_pending
| if VM_FAULT_RETRY
| return <-- not same case as above, but still OK since
| core mm already relinq lock for FAULT_RETRY
| ...
|
| < Now falls through for bug case above >
|
| up_read() <-- lock relinquished
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The motivation for this change was lockdep splat like below.
| potentially unexpected fatal signal 11.
| BUG: sleeping function called from invalid context at ../mm/page_alloc.c:4317
| in_atomic(): 1, irqs_disabled(): 0, pid: 57, name: segv
| no locks held by segv/57.
| Preemption disabled at:
| [<8182f17e>] get_signal+0x4a6/0x7c4
| CPU: 0 PID: 57 Comm: segv Not tainted 4.17.0+ #23
|
| Stack Trace:
| arc_unwind_core.constprop.1+0xd0/0xf4
| __might_sleep+0x1f6/0x234
| __get_free_pages+0x174/0xca0
| show_regs+0x22/0x330
| get_signal+0x4ac/0x7c4 # print_fatal_signals() -> preempt_disable()
| do_signal+0x30/0x224
| resume_user_mode_begin+0x90/0xd8
So signal handling core calls show_regs() with preemption disabled but
an ensuing GFP_KERNEL page allocator call is flagged by lockdep.
We could have switched to GFP_NOWAIT, but turns out that is not enough
anways and eliding page allocator call leads to less code and
instruction traces to sift thru when debugging pesky crashes.
FWIW, this patch doesn't cure the lockdep splat (which next patch does).
Reviewed-by: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
projects / thirdparty / kernel / stable.git / log
