posix_acl_update_mode checks to see if the permissions
described by the ACL can be encoded into the
object's mode. If so, it sets "acl" to NULL
and "mode" to the new desired value. Prior to this patch
we failed to actually propagate the new mode back to the
server.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0'). However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.
Fix the problem by creating __orangefs_set_acl() function that does not
call posix_acl_update_mode() and use it when inheriting ACLs. That
prevents SGID bit clearing and the mode has been properly set by
posix_acl_create() anyway.
Fixes: 073931017b
CC: stable@vger.kernel.org
CC: Mike Marshall <hubcap@omnibond.com>
CC: pvfs2-developers@beowulf-underground.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Several users have complained that the tile table update broke Oland
support. Despite several attempts to fix it, the root cause is still
unknown at this point and no solution is available. As it is not
acceptable to leave a known regression breaking a major functionality
in the kernel for several releases, let's just reverse this
optimization for now. It can be implemented again later if and only
if the breakage is understood and fixed.
As there were no complaints for Hainan so far, only the Oland part of
the offending commit is reverted. Optimization is preserved on
Hainan, so this commit isn't an actual revert of the original.
This fixes bug #194761:
https://bugzilla.kernel.org/show_bug.cgi?id=194761
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: f8d9422ef8 ("drm/amdgpu: update tile table for oland/hainan")
Cc: Flora Cui <Flora.Cui@amd.com>
Cc: Junwei Zhang <Jerry.Zhang@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Marek Olšák <maraeo@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
tnapi is being initialized and then immediately updated and
hence the initialiation is redundant. Clean up the warning
by moving the declaration and initialization to the inside
of the for-loop.
Cleans up clang scan-build warning:
warning: Value stored to 'tnapi' during its initialization is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that we have added breaks in the wait queue scan and allow bookmark
on scan position, we put this logic in the wake_up_page_bit function.
We can have very long page wait list in large system where multiple
pages share the same wait list. We break the wake up walk here to allow
other cpus a chance to access the list, and not to disable the interrupts
when traversing the list for too long. This reduces the interrupt and
rescheduling latency, and excessive page wait queue lock hold time.
[ v2: Remove bookmark_wake_function ]
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We encountered workloads that have very long wake up list on large
systems. A waker takes a long time to traverse the entire wake list and
execute all the wake functions.
We saw page wait list that are up to 3700+ entries long in tests of
large 4 and 8 socket systems. It took 0.8 sec to traverse such list
during wake up. Any other CPU that contends for the list spin lock will
spin for a long time. It is a result of the numa balancing migration of
hot pages that are shared by many threads.
Multiple CPUs waking are queued up behind the lock, and the last one
queued has to wait until all CPUs did all the wakeups.
The page wait list is traversed with interrupt disabled, which caused
various problems. This was the original cause that triggered the NMI
watch dog timer in: https://patchwork.kernel.org/patch/9800303/ . Only
extending the NMI watch dog timer there helped.
This patch bookmarks the waker's scan position in wake list and break
the wake up walk, to allow access to the list before the waker resume
its walk down the rest of the wait list. It lowers the interrupt and
rescheduling latency.
This patch also provides a performance boost when combined with the next
patch to break up page wakeup list walk. We saw 22% improvement in the
will-it-scale file pread2 test on a Xeon Phi system running 256 threads.
[ v2: Merged in Linus' changes to remove the bookmark_wake_function, and
simply access to flags. ]
Reported-by: Kan Liang <kan.liang@intel.com>
Tested-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make the needlessly global function tls_sw_free_resources static to fix
a gcc/sparse warning.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
qemu-system-x86-8600 [004] d..1 7205.687530: kvm_entry: vcpu 2
qemu-system-x86-8600 [004] .... 7205.687532: kvm_exit: reason EXCEPTION_NMI rip 0xffffffffa921297d info ffffeb2c0e44e018 80000b0e
qemu-system-x86-8600 [004] .... 7205.687532: kvm_page_fault: address ffffeb2c0e44e018 error_code 0
qemu-system-x86-8600 [004] .... 7205.687620: kvm_try_async_get_page: gva = 0xffffeb2c0e44e018, gfn = 0x427e4e
qemu-system-x86-8600 [004] .N.. 7205.687628: kvm_async_pf_not_present: token 0x8b002 gva 0xffffeb2c0e44e018
kworker/4:2-7814 [004] .... 7205.687655: kvm_async_pf_completed: gva 0xffffeb2c0e44e018 address 0x7fcc30c4e000
qemu-system-x86-8600 [004] .... 7205.687703: kvm_async_pf_ready: token 0x8b002 gva 0xffffeb2c0e44e018
qemu-system-x86-8600 [004] d..1 7205.687711: kvm_entry: vcpu 2
After running some memory intensive workload in guest, I catch the kworker
which completes the GUP too quickly, and queues an "Page Ready" #PF exception
after the "Page not Present" exception before the next vmentry as the above
trace which will result in #DF injected to guest.
This patch fixes it by clearing the queue for "Page not Present" if "Page Ready"
occurs before the next vmentry since the GUP has already got the required page
and shadow page table has already been fixed by "Page Ready" handler.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Fixes: 7c90705bf2 ("KVM: Inject asynchronous page fault into a PV guest if page is swapped out.")
[Changed indentation and added clearing of injected. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
SVM AVIC hardware accelerates guest write to APIC_EOI register
(for edge-trigger interrupt), which means it does not trap to KVM.
So, only enable SVM AVIC only in split irqchip mode.
(e.g. launching qemu w/ option '-machine kernel_irqchip=split').
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Fixes: 44a95dae1d ("KVM: x86: Detect and Initialize AVIC support")
[Removed pr_debug - Radim.]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
... and __initconst if applicable.
Based on similar work for an older kernel in the Grsecurity patch.
[JD: fix toshiba-wmi build]
[JD: add htcpen]
[JD: move __initconst where checkscript wants it]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
The lockup detector reconfiguration tears down all watchdog threads when
the watchdog is disabled and sets them up again when its enabled.
That's a pointless exercise. The watchdog threads are not consuming an
insane amount of resources, so it's enough to set them up at init time and
keep them in parked position when the watchdog is disabled and unpark them
when it is reenabled. The smpboot thread infrastructure takes care of
keeping the force parked threads in place even across cpu hotplug.
Aside of that the code implements the park/unpark facility of smp hotplug
threads on its own, which is even more pointless. We have functionality in
the smpboot thread code to do so.
Use the new thread management functions and get rid of the unholy mess.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Link: http://lkml.kernel.org/r/20170912194147.470370113@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The lockup detector reconfiguration tears down all watchdog threads when
the watchdog is disabled and sets them up again when its enabled.
That's a pointless exercise. The watchdog threads are not consuming an
insane amount of resources, so it's enough to set them up at init time and
keep them in parked position when the watchdog is disabled and unpark them
when it is reenabled. The smpboot thread infrastructure takes care of
keeping the force parked threads in place even across cpu hotplug.
Another horrible mechanism are the open coded park/unpark loops which are
used for reconfiguration of the watchdog. The smpboot infrastructure allows
exactly the same via smpboot_update_cpumask_thread_percpu(), which is cpu
hotplug safe. Using that instead of the open coded loops allows to get rid
of the hotplug locking mess in the watchdog code.
Implement a clean infrastructure which allows to replace the open coded
nonsense.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Link: http://lkml.kernel.org/r/20170912194147.377182587@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
b94f51183b ("kernel/watchdog: prevent false hardlockup on overloaded system")
tries to fix the following issue:
proc_write()
set_sample_period() <--- New sample period becoms visible
<----- Broken starts
proc_watchdog_update()
watchdog_enable_all_cpus() watchdog_hrtimer_fn()
update_watchdog_all_cpus() restart_timer(sample_period)
watchdog_park_threads()
thread->park()
disable_nmi()
<----- Broken ends
The reason why this is broken is that the update of the watchdog threshold
becomes immediately effective and visible for the hrtimer function which
uses that value to rearm the timer. But the NMI/perf side still uses the
old value up to the point where it is disabled. If the rate has been
lowered then the NMI can run fast enough to 'detect' a hard lockup because
the timer has not fired due to the longer period.
The patch 'fixed' this by adding a variable:
proc_write()
set_sample_period()
<----- Broken starts
proc_watchdog_update()
watchdog_enable_all_cpus() watchdog_hrtimer_fn()
update_watchdog_all_cpus() restart_timer(sample_period)
watchdog_park_threads()
park_in_progress = 1
<----- Broken ends
nmi_watchdog()
if (park_in_progress)
return;
The only effect of this variable was to make the window where the breakage
can hit small enough that it was not longer observable in testing. From a
correctness point of view it is a pointless bandaid which merily papers
over the root cause: the unsychronized update of the variable.
Looking deeper into the related code pathes unearthed similar problems in
the watchdog_start()/stop() functions.
watchdog_start()
perf_nmi_event_start()
hrtimer_start()
watchdog_stop()
hrtimer_cancel()
perf_nmi_event_stop()
In both cases the call order is wrong because if the tasks gets preempted
or the VM gets scheduled out long enough after the first call, then there is
a chance that the next NMI will see a stale hrtimer interrupt count and
trigger a false positive hard lockup splat.
Get rid of park_in_progress so the code can be gradually deobfuscated and
pruned from several layers of duct tape papering over the root cause,
which has been either ignored or not understood at all.
Once this is removed the underlying problem will be fixed by rewriting the
proc interface to do a proper synchronized update.
Address the start/stop() ordering problem as well by reverting the call
order, so this part is at least correct now.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1709052038270.2393@nanos
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The following deadlock is possible in the watchdog hotplug code:
cpus_write_lock()
...
takedown_cpu()
smpboot_park_threads()
smpboot_park_thread()
kthread_park()
->park() := watchdog_disable()
watchdog_nmi_disable()
perf_event_release_kernel();
put_event()
_free_event()
->destroy() := hw_perf_event_destroy()
x86_release_hardware()
release_ds_buffers()
get_online_cpus()
when a per cpu watchdog perf event is destroyed which drops the last
reference to the PMU hardware. The cleanup code there invokes
get_online_cpus() which instantly deadlocks because the hotplug percpu
rwsem is write locked.
To solve this add a deferring mechanism:
cpus_write_lock()
kthread_park()
watchdog_nmi_disable(deferred)
perf_event_disable(event);
move_event_to_deferred(event);
....
cpus_write_unlock()
cleaup_deferred_events()
perf_event_release_kernel()
This is still properly serialized against concurrent hotplug via the
cpu_add_remove_lock, which is held by the task which initiated the hotplug
event.
This is also used to handle event destruction when the watchdog threads are
parked via other mechanisms than CPU hotplug.
Analyzed-by: Peter Zijlstra <peterz@infradead.org>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Link: http://lkml.kernel.org/r/20170912194146.884469246@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The self disabling feature is broken vs. CPU hotplug locking:
CPU 0 CPU 1
cpus_write_lock();
cpu_up(1)
wait_for_completion()
....
unpark_watchdog()
->unpark()
perf_event_create() <- fails
watchdog_enable &= ~NMI_WATCHDOG;
....
cpus_write_unlock();
CPU 2
cpus_write_lock()
cpu_down(2)
wait_for_completion()
wakeup(watchdog);
watchdog()
if (!(watchdog_enable & NMI_WATCHDOG))
watchdog_nmi_disable()
perf_event_disable()
....
cpus_read_lock();
stop_smpboot_threads()
park_watchdog();
wait_for_completion(watchdog->parked);
Result: End of hotplug and instantaneous full lockup of the machine.
There is a similar problem with disabling the watchdog via the user space
interface as the sysctl function fiddles with watchdog_enable directly.
It's very debatable whether this is required at all. If the watchdog works
nicely on N CPUs and it fails to enable on the N + 1 CPU either during
hotplug or because the user space interface disabled it via sysctl cpumask
and then some perf user grabbed the counter which is then unavailable for
the watchdog when the sysctl cpumask gets changed back.
There is no real justification for this.
One of the reasons WHY this is done is the utter stupidity of the init code
of the perf NMI watchdog. Instead of checking upfront at boot whether PERF
is available and functional at all, it just does this check at run time
over and over when user space fiddles with the sysctl. That's broken beyond
repair along with the idiotic error code dependent warn level printks and
the even more silly printk rate limiting.
If the init code checks whether perf works at boot time, then this mess can
be more or less avoided completely. Perf does not come magically into life
at runtime. Brain usage while coding is overrated.
Remove the cruft and add a temporary safe guard which gets removed later.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Link: http://lkml.kernel.org/r/20170912194146.806708429@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The page_owner stacktrace always begin as follows:
[<ffffff987bfd48f4>] save_stack+0x40/0xc8
[<ffffff987bfd4da8>] __set_page_owner+0x3c/0x6c
These two entries do not provide any useful information and limits the
available stacktrace depth. The page_owner stacktrace was skipping
caller function from stack entries but this was missed with commit
f2ca0b5571 ("mm/page_owner: use stackdepot to store stacktrace")
Example page_owner entry after the patch:
Page allocated via order 0, mask 0x8(ffffff80085fb714)
PFN 654411 type Movable Block 639 type CMA Flags 0x0(ffffffbe5c7f12c0)
[<ffffff9b64989c14>] post_alloc_hook+0x70/0x80
...
[<ffffff9b651216e8>] msm_comm_try_state+0x5f8/0x14f4
[<ffffff9b6512486c>] msm_vidc_open+0x5e4/0x7d0
[<ffffff9b65113674>] msm_v4l2_open+0xa8/0x224
Link: http://lkml.kernel.org/r/1504078343-28754-2-git-send-email-guptap@codeaurora.org
Fixes: f2ca0b5571 ("mm/page_owner: use stackdepot to store stacktrace")
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The stacktraces always begin as follows:
[<c00117b4>] save_stack_trace_tsk+0x0/0x98
[<c0011870>] save_stack_trace+0x24/0x28
...
This is because the stack trace code includes the stack frames for
itself. This is incorrect behaviour, and also leads to "skip" doing the
wrong thing (which is the number of stack frames to avoid recording.)
Perversely, it does the right thing when passed a non-current thread.
Fix this by ensuring that we have a known constant number of frames
above the main stack trace function, and always skip these.
This was fixed for arch arm by commit 3683f44c42 ("ARM: stacktrace:
avoid listing stacktrace functions in stacktrace")
Link: http://lkml.kernel.org/r/1504078343-28754-1-git-send-email-guptap@codeaurora.org
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
GFP_TEMPORARY was introduced by commit e12ba74d8f ("Group short-lived
and reclaimable kernel allocations") along with __GFP_RECLAIMABLE. It's
primary motivation was to allow users to tell that an allocation is
short lived and so the allocator can try to place such allocations close
together and prevent long term fragmentation. As much as this sounds
like a reasonable semantic it becomes much less clear when to use the
highlevel GFP_TEMPORARY allocation flag. How long is temporary? Can the
context holding that memory sleep? Can it take locks? It seems there is
no good answer for those questions.
The current implementation of GFP_TEMPORARY is basically GFP_KERNEL |
__GFP_RECLAIMABLE which in itself is tricky because basically none of
the existing caller provide a way to reclaim the allocated memory. So
this is rather misleading and hard to evaluate for any benefits.
I have checked some random users and none of them has added the flag
with a specific justification. I suspect most of them just copied from
other existing users and others just thought it might be a good idea to
use without any measuring. This suggests that GFP_TEMPORARY just
motivates for cargo cult usage without any reasoning.
I believe that our gfp flags are quite complex already and especially
those with highlevel semantic should be clearly defined to prevent from
confusion and abuse. Therefore I propose dropping GFP_TEMPORARY and
replace all existing users to simply use GFP_KERNEL. Please note that
SLAB users with shrinkers will still get __GFP_RECLAIMABLE heuristic and
so they will be placed properly for memory fragmentation prevention.
I can see reasons we might want some gfp flag to reflect shorterm
allocations but I propose starting from a clear semantic definition and
only then add users with proper justification.
This was been brought up before LSF this year by Matthew [1] and it
turned out that GFP_TEMPORARY really doesn't have a clear semantic. It
seems to be a heuristic without any measured advantage for most (if not
all) its current users. The follow up discussion has revealed that
opinions on what might be temporary allocation differ a lot between
developers. So rather than trying to tweak existing users into a
semantic which they haven't expected I propose to simply remove the flag
and start from scratch if we really need a semantic for short term
allocations.
[1] http://lkml.kernel.org/r/20170118054945.GD18349@bombadil.infradead.org
[akpm@linux-foundation.org: fix typo]
[akpm@linux-foundation.org: coding-style fixes]
[sfr@canb.auug.org.au: drm/i915: fix up]
Link: http://lkml.kernel.org/r/20170816144703.378d4f4d@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170728091904.14627-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Neil Brown <neilb@suse.de>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc-7 points out that a negative port_num value would overflow the
string buffer:
drivers/infiniband/hw/mlx4/sysfs.c: In function 'mlx4_ib_device_register_sysfs':
drivers/infiniband/hw/mlx4/sysfs.c:251:16: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=]
drivers/infiniband/hw/mlx4/sysfs.c:251:2: note: 'sprintf' output between 2 and 11 bytes into a destination of size 10
drivers/infiniband/hw/mlx4/sysfs.c:303:17: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=]
drivers/infiniband/hw/mlx4/sysfs.c:303:3: note: 'sprintf' output between 2 and 11 bytes into a destination of size 10
While we should be able to assume that port_num is positive here, making
the buffer one byte longer has no downsides and avoids the warning.
Fixes: c1e7e46612 ("IB/mlx4: Add iov directory in sysfs under the ib device")
Link: http://lkml.kernel.org/r/20170714120720.906842-23-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc points out a minor bug in the handling of unknown cookie types,
which could result in a string overflow when the integer is copied into
a 3-byte string:
fs/fscache/object-list.c: In function 'fscache_objlist_show':
fs/fscache/object-list.c:265:19: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=]
sprintf(_type, "%02u", cookie->def->type);
^~~~~~
fs/fscache/object-list.c:265:4: note: 'sprintf' output between 3 and 4 bytes into a destination of size 3
This is currently harmless as no code sets a type other than 0 or 1, but
it makes sense to use snprintf() here to avoid overflowing the array if
that changes.
Link: http://lkml.kernel.org/r/20170714120720.906842-22-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
