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e8857288bb
33474 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Sumit Garg
|
e8857288bb |
kdb: Check status of console prior to invoking handlers
Check if a console is enabled prior to invoking corresponding write handler. Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Sumit Garg <sumit.garg@linaro.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/1591264879-25920-3-git-send-email-sumit.garg@linaro.org Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> |
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Sumit Garg
|
9d71b344f8 |
kdb: Re-factor kdb_printf() message write code
Re-factor kdb_printf() message write code in order to avoid duplication of code and thereby increase readability. Signed-off-by: Sumit Garg <sumit.garg@linaro.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/1591264879-25920-2-git-send-email-sumit.garg@linaro.org Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> |
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Linus Torvalds
|
8b6ddd10d6 |
A few fixes and small cleanups for tracing:
- Have recordmcount work with > 64K sections (to support LTO) - kprobe RCU fixes - Correct a kprobe critical section with missing mutex - Remove redundant arch_disarm_kprobe() call - Fix lockup when kretprobe triggers within kprobe_flush_task() - Fix memory leak in fetch_op_data operations - Fix sleep in atomic in ftrace trace array sample code - Free up memory on failure in sample trace array code - Fix incorrect reporting of function_graph fields in format file - Fix quote within quote parsing in bootconfig - Fix return value of bootconfig tool - Add testcases for bootconfig tool - Fix maybe uninitialized warning in ftrace pid file code - Remove unused variable in tracing_iter_reset() - Fix some typos -----BEGIN PGP SIGNATURE----- iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXu1jrRQccm9zdGVkdEBn b29kbWlzLm9yZwAKCRAp5XQQmuv6qoCMAP91nOccE3X+Nvc3zET3isDWnl1tWJxk icsBgN/JwBRuTAD/dnWTHIWM2/5lTiagvyVsmINdJHP6JLr8T7dpN9tlxAQ= =Cuo7 -----END PGP SIGNATURE----- Merge tag 'trace-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: - Have recordmcount work with > 64K sections (to support LTO) - kprobe RCU fixes - Correct a kprobe critical section with missing mutex - Remove redundant arch_disarm_kprobe() call - Fix lockup when kretprobe triggers within kprobe_flush_task() - Fix memory leak in fetch_op_data operations - Fix sleep in atomic in ftrace trace array sample code - Free up memory on failure in sample trace array code - Fix incorrect reporting of function_graph fields in format file - Fix quote within quote parsing in bootconfig - Fix return value of bootconfig tool - Add testcases for bootconfig tool - Fix maybe uninitialized warning in ftrace pid file code - Remove unused variable in tracing_iter_reset() - Fix some typos * tag 'trace-v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Fix maybe-uninitialized compiler warning tools/bootconfig: Add testcase for show-command and quotes test tools/bootconfig: Fix to return 0 if succeeded to show the bootconfig tools/bootconfig: Fix to use correct quotes for value proc/bootconfig: Fix to use correct quotes for value tracing: Remove unused event variable in tracing_iter_reset tracing/probe: Fix memleak in fetch_op_data operations trace: Fix typo in allocate_ftrace_ops()'s comment tracing: Make ftrace packed events have align of 1 sample-trace-array: Remove trace_array 'sample-instance' sample-trace-array: Fix sleeping function called from invalid context kretprobe: Prevent triggering kretprobe from within kprobe_flush_task kprobes: Remove redundant arch_disarm_kprobe() call kprobes: Fix to protect kick_kprobe_optimizer() by kprobe_mutex kprobes: Use non RCU traversal APIs on kprobe_tables if possible kprobes: Suppress the suspicious RCU warning on kprobes recordmcount: support >64k sections |
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Linus Torvalds
|
d2b1c81f5f |
block-5.8-2020-06-19
-----BEGIN PGP SIGNATURE----- iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl7s0SAQHGF4Ym9lQGtl cm5lbC5kawAKCRD301j7KXHgpp+YEACVqFvsfzxKCqa61IzyuOaPfnj9awyP+MY2 7V6y9sDDHL8sp6aPDbHvqFnqz0O7E+7nHVZD2rf2qc6tKKMvJYNO/BFZSXPvWTZV KQ4cBChf/LDwqAKOnI4ZhmF5UcSyyob1yMy4uJ+U0gQiXXrRMbwJ3N1K24a9dr4c epkzGavR0Q+PJ9BbUgjACjbRdT+vrP4bOu0cuyCGkIpD9eCerKJ6mFaUAj0FDthD bg4BJj+c8Ij6LO0V++Wga6OxccmL43KeP0ky8B3x07PfAl+tDWqsbHSlU2YPtdcq 5nKgMMTW16mVnZeO2/W0JB7tn89VubsmyvIFcm2KNeeRqSnEZyW9HI8n4kq994Ju xMH24lgbsU4trNeYkgOmzPoJJZ+LShkn+rnldyI1U/fhpEYub7DqfVySuT7ti9in uFpQdeRUmPsdw92F3+o6h8OYAflpcQQ7CblkzxPEeV4OyzOZasb+S9tMNPe59KBh 0MtHv9IfzgtDihR6HuXifitXaP+GtH4x3D2z0dzEdooHKHC/+P3WycS5daG+3WKQ xV5lJruvpTuxhXKLFAH0wRrxnVlB0VUvhQ21T3WgHrwF0btbdmQMHFc83XOxBIB4 jHWJMHGc4xp1ZdpWFBC8Cj79OmJh1w/ao8+/cf8SUoTB0LzFce1B8LvwnxgpcpUk VjIOrl7zhQ== =LeLd -----END PGP SIGNATURE----- Merge tag 'block-5.8-2020-06-19' of git://git.kernel.dk/linux-block Pull block fixes from Jens Axboe: - Use import_uuid() where appropriate (Andy) - bcache fixes (Coly, Mauricio, Zhiqiang) - blktrace sparse warnings fix (Jan) - blktrace concurrent setup fix (Luis) - blkdev_get use-after-free fix (Jason) - Ensure all blk-mq maps are updated (Weiping) - Loop invalidate bdev fix (Zheng) * tag 'block-5.8-2020-06-19' of git://git.kernel.dk/linux-block: block: make function 'kill_bdev' static loop: replace kill_bdev with invalidate_bdev partitions/ldm: Replace uuid_copy() with import_uuid() where it makes sense block: update hctx map when use multiple maps blktrace: Avoid sparse warnings when assigning q->blk_trace blktrace: break out of blktrace setup on concurrent calls block: Fix use-after-free in blkdev_get() trace/events/block.h: drop kernel-doc for dropped function parameter blk-mq: Remove redundant 'return' statement bcache: pr_info() format clean up in bcache_device_init() bcache: use delayed kworker fo asynchronous devices registration bcache: check and adjust logical block size for backing devices bcache: fix potential deadlock problem in btree_gc_coalesce |
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Linus Torvalds
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5e857ce6ea |
Merge branch 'hch' (maccess patches from Christoph Hellwig)
Merge non-faulting memory access cleanups from Christoph Hellwig:
"Andrew and I decided to drop the patches implementing your suggested
rename of the probe_kernel_* and probe_user_* helpers from -mm as
there were way to many conflicts.
After -rc1 might be a good time for this as all the conflicts are
resolved now"
This also adds a type safety checking patch on top of the renaming
series to make the subtle behavioral difference between 'get_user()' and
'get_kernel_nofault()' less potentially dangerous and surprising.
* emailed patches from Christoph Hellwig <hch@lst.de>:
maccess: make get_kernel_nofault() check for minimal type compatibility
maccess: rename probe_kernel_address to get_kernel_nofault
maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofault
maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
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Kaitao Cheng
|
026bb845b0 |
ftrace: Fix maybe-uninitialized compiler warning
During build compiler reports some 'false positive' warnings about
variables {'seq_ops', 'filtered_pids', 'other_pids'} may be used
uninitialized. This patch silences these warnings.
Also delete some useless spaces
Link: https://lkml.kernel.org/r/20200529141214.37648-1-pilgrimtao@gmail.com
Signed-off-by: Kaitao Cheng <pilgrimtao@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Linus Torvalds
|
1b50440210 |
dma-mapping fixes for 5.8
- fixes for the SEV atomic pool (Geert Uytterhoeven and David Rientjes) -----BEGIN PGP SIGNATURE----- iQI/BAABCgApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAl7pxQwLHGhjaEBsc3Qu ZGUACgkQD55TZVIEUYN7kg/9F/S+fE587iJhn+6LbJHyNiAWtASi+cogBoO+Qdx/ GDby8YP+s2+6hxIskavfdCSzY6W3UbCslgwxeZNKD60semb8BacAtf55N2PEK0/H UE8J9d/EInbe1ehrJvd7xCcuWxkesHGa/zcFbMBPvXxphX6SNfgPV0fdgg3UuWM9 ZxRPENA14hXOF2ehKnbQNHcgodOm6SGM22PEk3g8GqASc2zCL+E+CVcRVFgoYmzw BgRgv5CaaHCHGvmWWtN4wWNmOm5YCqYmMuEAElbuWhY6VhcPVirMVtLju+3RfSmY 1QEQQ0jQRtlQe9SuqhUPiegtReFMIvwC0Aoip7FaCSVMMean6uSzk3ubapkigCza r5dwG6RiLzVpRJyoYbDhCHh7gOUsXTMXqUzy33Jr5bTbGSJcelbycehL7gP9Qzag fFQ9Yep+BLDYESf7H5KzhDv9siZqGX2kXj3Z/gJGGMjkCUeAKNviRsi9t/IhQuzt cVAJCcU9vLJk2MJRuQ0P/7lCDvUIR4yGalN9Jl9J1ZTsVR7go330RVvonPhlTcXX 9HrroqzSkqnLfaUFB3ml3LHj4SqygfUGtjbJ6qxkXxrChMfySe/VWbBrmOVUlta3 SfKfXRcEYeHlgS7TtkxHkstaXfVA+fKN7V//PoycP9+rvoX74e2h++ujUY9kf8xJ QPQ= =uKpw -----END PGP SIGNATURE----- Merge tag 'dma-mapping-5.8-3' of git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping fixes from Christoph Hellwig: "Fixes for the SEV atomic pool (Geert Uytterhoeven and David Rientjes)" * tag 'dma-mapping-5.8-3' of git://git.infradead.org/users/hch/dma-mapping: dma-pool: decouple DMA_REMAP from DMA_COHERENT_POOL dma-pool: fix too large DMA pools on medium memory size systems |
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Christoph Hellwig
|
c0ee37e85e |
maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofault
Better describe what these functions do. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Christoph Hellwig
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fe557319aa |
maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
Better describe what these functions do. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Jan Kara
|
c3dbe541ef |
blktrace: Avoid sparse warnings when assigning q->blk_trace
Mostly for historical reasons, q->blk_trace is assigned through xchg()
and cmpxchg() atomic operations. Although this is correct, sparse
complains about this because it violates rcu annotations since commit
|
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Luis Chamberlain
|
1b0b283648 |
blktrace: break out of blktrace setup on concurrent calls
We use one blktrace per request_queue, that means one per the entire disk. So we cannot run one blktrace on say /dev/vda and then /dev/vda1, or just two calls on /dev/vda. We check for concurrent setup only at the very end of the blktrace setup though. If we try to run two concurrent blktraces on the same block device the second one will fail, and the first one seems to go on. However when one tries to kill the first one one will see things like this: The kernel will show these: ``` debugfs: File 'dropped' in directory 'nvme1n1' already present! debugfs: File 'msg' in directory 'nvme1n1' already present! debugfs: File 'trace0' in directory 'nvme1n1' already present! `` And userspace just sees this error message for the second call: ``` blktrace /dev/nvme1n1 BLKTRACESETUP(2) /dev/nvme1n1 failed: 5/Input/output error ``` The first userspace process #1 will also claim that the files were taken underneath their nose as well. The files are taken away form the first process given that when the second blktrace fails, it will follow up with a BLKTRACESTOP and BLKTRACETEARDOWN. This means that even if go-happy process #1 is waiting for blktrace data, we *have* been asked to take teardown the blktrace. This can easily be reproduced with break-blktrace [0] run_0005.sh test. Just break out early if we know we're already going to fail, this will prevent trying to create the files all over again, which we know still exist. [0] https://github.com/mcgrof/break-blktrace Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> |
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YangHui
|
69243720c0 |
tracing: Remove unused event variable in tracing_iter_reset
We do not use the event variable, just remove it. Signed-off-by: YangHui <yanghui.def@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> |
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Vamshi K Sthambamkadi
|
3aa8fdc37d |
tracing/probe: Fix memleak in fetch_op_data operations
kmemleak report:
[<57dcc2ca>] __kmalloc_track_caller+0x139/0x2b0
[<f1c45d0f>] kstrndup+0x37/0x80
[<f9761eb0>] parse_probe_arg.isra.7+0x3cc/0x630
[<055bf2ba>] traceprobe_parse_probe_arg+0x2f5/0x810
[<655a7766>] trace_kprobe_create+0x2ca/0x950
[<4fc6a02a>] create_or_delete_trace_kprobe+0xf/0x30
[<6d1c8a52>] trace_run_command+0x67/0x80
[<be812cc0>] trace_parse_run_command+0xa7/0x140
[<aecfe401>] probes_write+0x10/0x20
[<2027641c>] __vfs_write+0x30/0x1e0
[<6a4aeee1>] vfs_write+0x96/0x1b0
[<3517fb7d>] ksys_write+0x53/0xc0
[<dad91db7>] __ia32_sys_write+0x15/0x20
[<da347f64>] do_syscall_32_irqs_on+0x3d/0x260
[<fd0b7e7d>] do_fast_syscall_32+0x39/0xb0
[<ea5ae810>] entry_SYSENTER_32+0xaf/0x102
Post parse_probe_arg(), the FETCH_OP_DATA operation type is overwritten
to FETCH_OP_ST_STRING, as a result memory is never freed since
traceprobe_free_probe_arg() iterates only over SYMBOL and DATA op types
Setup fetch string operation correctly after fetch_op_data operation.
Link: https://lkml.kernel.org/r/20200615143034.GA1734@cosmos
Cc: stable@vger.kernel.org
Fixes:
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Wei Yang
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48a42f5d13 |
trace: Fix typo in allocate_ftrace_ops()'s comment
No functional change, just correct the word. Link: https://lkml.kernel.org/r/20200610033251.31713-1-richard.weiyang@linux.alibaba.com Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> |
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Steven Rostedt (VMware)
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4649079b9d |
tracing: Make ftrace packed events have align of 1
When using trace-cmd on 5.6-rt for the function graph tracer, the output was
corrupted. It gave output like this:
funcgraph_entry: func=0xffffffff depth=38982
funcgraph_entry: func=0x1ffffffff depth=16044
funcgraph_exit: func=0xffffffff overrun=0x92539aaf00000000 calltime=0x92539c9900000072 rettime=0x100000072 depth=11084
funcgraph_exit: func=0xffffffff overrun=0x9253946e00000000 calltime=0x92539e2100000072 rettime=0x72 depth=26033702
funcgraph_entry: func=0xffffffff depth=85798
funcgraph_entry: func=0x1ffffffff depth=12044
The reason was because the tracefs/events/ftrace/funcgraph_entry/exit format
file was incorrect. The -rt kernel adds more common fields to the trace
events. Namely, common_migrate_disable and common_preempt_lazy_count. Each
is one byte in size. This changes the alignment of the normal payload. Most
events are aligned normally, but the function and function graph events are
defined with a "PACKED" macro, that packs their payload. As the offsets
displayed in the format files are now calculated by an aligned field, the
aligned field for function and function graph events should be 1, not their
normal alignment.
With aligning of the funcgraph_entry event, the format file has:
field:unsigned short common_type; offset:0; size:2; signed:0;
field:unsigned char common_flags; offset:2; size:1; signed:0;
field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
field:int common_pid; offset:4; size:4; signed:1;
field:unsigned char common_migrate_disable; offset:8; size:1; signed:0;
field:unsigned char common_preempt_lazy_count; offset:9; size:1; signed:0;
field:unsigned long func; offset:16; size:8; signed:0;
field:int depth; offset:24; size:4; signed:1;
But the actual alignment is:
field:unsigned short common_type; offset:0; size:2; signed:0;
field:unsigned char common_flags; offset:2; size:1; signed:0;
field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
field:int common_pid; offset:4; size:4; signed:1;
field:unsigned char common_migrate_disable; offset:8; size:1; signed:0;
field:unsigned char common_preempt_lazy_count; offset:9; size:1; signed:0;
field:unsigned long func; offset:12; size:8; signed:0;
field:int depth; offset:20; size:4; signed:1;
Link: https://lkml.kernel.org/r/20200609220041.2a3b527f@oasis.local.home
Cc: stable@vger.kernel.org
Fixes:
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Jiri Olsa
|
9b38cc704e |
kretprobe: Prevent triggering kretprobe from within kprobe_flush_task
Ziqian reported lockup when adding retprobe on _raw_spin_lock_irqsave.
My test was also able to trigger lockdep output:
============================================
WARNING: possible recursive locking detected
5.6.0-rc6+ #6 Not tainted
--------------------------------------------
sched-messaging/2767 is trying to acquire lock:
ffffffff9a492798 (&(kretprobe_table_locks[i].lock)){-.-.}, at: kretprobe_hash_lock+0x52/0xa0
but task is already holding lock:
ffffffff9a491a18 (&(kretprobe_table_locks[i].lock)){-.-.}, at: kretprobe_trampoline+0x0/0x50
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&(kretprobe_table_locks[i].lock));
lock(&(kretprobe_table_locks[i].lock));
*** DEADLOCK ***
May be due to missing lock nesting notation
1 lock held by sched-messaging/2767:
#0: ffffffff9a491a18 (&(kretprobe_table_locks[i].lock)){-.-.}, at: kretprobe_trampoline+0x0/0x50
stack backtrace:
CPU: 3 PID: 2767 Comm: sched-messaging Not tainted 5.6.0-rc6+ #6
Call Trace:
dump_stack+0x96/0xe0
__lock_acquire.cold.57+0x173/0x2b7
? native_queued_spin_lock_slowpath+0x42b/0x9e0
? lockdep_hardirqs_on+0x590/0x590
? __lock_acquire+0xf63/0x4030
lock_acquire+0x15a/0x3d0
? kretprobe_hash_lock+0x52/0xa0
_raw_spin_lock_irqsave+0x36/0x70
? kretprobe_hash_lock+0x52/0xa0
kretprobe_hash_lock+0x52/0xa0
trampoline_handler+0xf8/0x940
? kprobe_fault_handler+0x380/0x380
? find_held_lock+0x3a/0x1c0
kretprobe_trampoline+0x25/0x50
? lock_acquired+0x392/0xbc0
? _raw_spin_lock_irqsave+0x50/0x70
? __get_valid_kprobe+0x1f0/0x1f0
? _raw_spin_unlock_irqrestore+0x3b/0x40
? finish_task_switch+0x4b9/0x6d0
? __switch_to_asm+0x34/0x70
? __switch_to_asm+0x40/0x70
The code within the kretprobe handler checks for probe reentrancy,
so we won't trigger any _raw_spin_lock_irqsave probe in there.
The problem is in outside kprobe_flush_task, where we call:
kprobe_flush_task
kretprobe_table_lock
raw_spin_lock_irqsave
_raw_spin_lock_irqsave
where _raw_spin_lock_irqsave triggers the kretprobe and installs
kretprobe_trampoline handler on _raw_spin_lock_irqsave return.
The kretprobe_trampoline handler is then executed with already
locked kretprobe_table_locks, and first thing it does is to
lock kretprobe_table_locks ;-) the whole lockup path like:
kprobe_flush_task
kretprobe_table_lock
raw_spin_lock_irqsave
_raw_spin_lock_irqsave ---> probe triggered, kretprobe_trampoline installed
---> kretprobe_table_locks locked
kretprobe_trampoline
trampoline_handler
kretprobe_hash_lock(current, &head, &flags); <--- deadlock
Adding kprobe_busy_begin/end helpers that mark code with fake
probe installed to prevent triggering of another kprobe within
this code.
Using these helpers in kprobe_flush_task, so the probe recursion
protection check is hit and the probe is never set to prevent
above lockup.
Link: http://lkml.kernel.org/r/158927059835.27680.7011202830041561604.stgit@devnote2
Fixes:
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Masami Hiramatsu
|
75ddf64dd2 |
kprobes: Remove redundant arch_disarm_kprobe() call
Fix to remove redundant arch_disarm_kprobe() call in force_unoptimize_kprobe(). This arch_disarm_kprobe() will be invoked if the kprobe is optimized but disabled, but that means the kprobe (optprobe) is unused (and unoptimized) state. In that case, unoptimize_kprobe() puts it in freeing_list and kprobe_optimizer (do_unoptimize_kprobes()) automatically disarm it. Thus this arch_disarm_kprobe() is redundant. Link: http://lkml.kernel.org/r/158927058719.27680.17183632908465341189.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> |
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Masami Hiramatsu
|
1a0aa991a6 |
kprobes: Fix to protect kick_kprobe_optimizer() by kprobe_mutex
In kprobe_optimizer() kick_kprobe_optimizer() is called
without kprobe_mutex, but this can race with other caller
which is protected by kprobe_mutex.
To fix that, expand kprobe_mutex protected area to protect
kick_kprobe_optimizer() call.
Link: http://lkml.kernel.org/r/158927057586.27680.5036330063955940456.stgit@devnote2
Fixes:
|
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|
Masami Hiramatsu
|
7e6a71d8e6 |
kprobes: Use non RCU traversal APIs on kprobe_tables if possible
Current kprobes uses RCU traversal APIs on kprobe_tables even if it is safe because kprobe_mutex is locked. Make those traversals to non-RCU APIs where the kprobe_mutex is locked. Link: http://lkml.kernel.org/r/158927056452.27680.9710575332163005121.stgit@devnote2 Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> |
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Masami Hiramatsu
|
6743ad432e |
kprobes: Suppress the suspicious RCU warning on kprobes
Anders reported that the lockdep warns that suspicious RCU list usage in register_kprobe() (detected by CONFIG_PROVE_RCU_LIST.) This is because get_kprobe() access kprobe_table[] by hlist_for_each_entry_rcu() without rcu_read_lock. If we call get_kprobe() from the breakpoint handler context, it is run with preempt disabled, so this is not a problem. But in other cases, instead of rcu_read_lock(), we locks kprobe_mutex so that the kprobe_table[] is not updated. So, current code is safe, but still not good from the view point of RCU. Joel suggested that we can silent that warning by passing lockdep_is_held() to the last argument of hlist_for_each_entry_rcu(). Add lockdep_is_held(&kprobe_mutex) at the end of the hlist_for_each_entry_rcu() to suppress the warning. Link: http://lkml.kernel.org/r/158927055350.27680.10261450713467997503.stgit@devnote2 Reported-by: Anders Roxell <anders.roxell@linaro.org> Suggested-by: Joel Fernandes <joel@joelfernandes.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> |
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Gustavo A. R. Silva
|
7fac96f2be |
tracing/probe: Replace zero-length array with flexible-array
There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://github.com/KSPP/linux/issues/21 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> |
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David Rientjes
|
dbed452a07 |
dma-pool: decouple DMA_REMAP from DMA_COHERENT_POOL
DMA_REMAP is an unnecessary requirement for AMD SEV, which requires
DMA_COHERENT_POOL, so avoid selecting it when it is otherwise unnecessary.
The only other requirement for DMA coherent pools is DMA_DIRECT_REMAP, so
ensure that properly selects the config option when needed.
Fixes:
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Linus Torvalds
|
4a87b197c1 |
Add additional LSM hooks for SafeSetID
SafeSetID is capable of making allow/deny decisions for set*uid calls on a system, and we want to add similar functionality for set*gid calls. The work to do that is not yet complete, so probably won't make it in for v5.8, but we are looking to get this simple patch in for v5.8 since we have it ready. We are planning on the rest of the work for extending the SafeSetID LSM being merged during the v5.9 merge window. This patch was sent to the security mailing list and there were no objections. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEgvWslnM+qUy+sgVg5n2WYw6TPBAFAl7mZCoACgkQ5n2WYw6T PBAk1RAAl8t3/m3lELf8qIir4OAd4nK0kc4e+7W8WkznX2ljUl2IetlNxDCBmEXr T5qoW6uPsr6kl5AKnbl9Ii7WpW/halsslpKSUNQCs6zbecoVdxekJ8ISW7xHuboZ SvS1bqm+t++PM0c0nWSFEr7eXYmPH8OGbCqu6/+nnbxPZf2rJX03e5LnHkEFDFnZ 0D/rsKgzMt01pdBJQXeoKk79etHO5MjuAkkYVEKJKCR1fM16lk7ECaCp0KJv1Mmx I88VncbLvI+um4t82d1Z8qDr2iLgogjJrMZC4WKfxDTmlmxox2Fz9ZJo+8sIWk6k T3a95x0s/mYCO4gWtpCVICt9+71Z3ie9T2iaI+CIe/kJvI/ysb+7LSkF+PD33bdz 0yv6Y9+VMRdzb3pW69R28IoP4wdYQOJRomsY49z6ypH0RgBWcBvyE6e4v+WJGRNK E164Imevf6rrZeqJ0kGSBS1nL9WmQHMaXabAwxg1jK1KRZD+YZj3EKC9S/+PAkaT 1qXUgvGuXHGjQrwU0hclQjgc6BAudWfAGdfrVr7IWwNKJmjgBf6C35my/azrkOg9 wHCEpUWVmZZLIZLM69/6QXdmMA+iR+rPz5qlVnWhWTfjRYJUXM455Zk+aNo+Qnwi +saCcdU+9xqreLeDIoYoebcV/ctHeW0XCQi/+ebjexXVlyeSfYs= =I+0L -----END PGP SIGNATURE----- Merge tag 'LSM-add-setgid-hook-5.8-author-fix' of git://github.com/micah-morton/linux Pull SafeSetID update from Micah Morton: "Add additional LSM hooks for SafeSetID SafeSetID is capable of making allow/deny decisions for set*uid calls on a system, and we want to add similar functionality for set*gid calls. The work to do that is not yet complete, so probably won't make it in for v5.8, but we are looking to get this simple patch in for v5.8 since we have it ready. We are planning on the rest of the work for extending the SafeSetID LSM being merged during the v5.9 merge window" * tag 'LSM-add-setgid-hook-5.8-author-fix' of git://github.com/micah-morton/linux: security: Add LSM hooks to set*gid syscalls |
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Thomas Cedeno
|
39030e1351 |
security: Add LSM hooks to set*gid syscalls
The SafeSetID LSM uses the security_task_fix_setuid hook to filter set*uid() syscalls according to its configured security policy. In preparation for adding analagous support in the LSM for set*gid() syscalls, we add the requisite hook here. Tested by putting print statements in the security_task_fix_setgid hook and seeing them get hit during kernel boot. Signed-off-by: Thomas Cedeno <thomascedeno@google.com> Signed-off-by: Micah Morton <mortonm@chromium.org> |
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|
Linus Torvalds
|
96144c58ab |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:
1) Fix cfg80211 deadlock, from Johannes Berg.
2) RXRPC fails to send norigications, from David Howells.
3) MPTCP RM_ADDR parsing has an off by one pointer error, fix from
Geliang Tang.
4) Fix crash when using MSG_PEEK with sockmap, from Anny Hu.
5) The ucc_geth driver needs __netdev_watchdog_up exported, from
Valentin Longchamp.
6) Fix hashtable memory leak in dccp, from Wang Hai.
7) Fix how nexthops are marked as FDB nexthops, from David Ahern.
8) Fix mptcp races between shutdown and recvmsg, from Paolo Abeni.
9) Fix crashes in tipc_disc_rcv(), from Tuong Lien.
10) Fix link speed reporting in iavf driver, from Brett Creeley.
11) When a channel is used for XSK and then reused again later for XSK,
we forget to clear out the relevant data structures in mlx5 which
causes all kinds of problems. Fix from Maxim Mikityanskiy.
12) Fix memory leak in genetlink, from Cong Wang.
13) Disallow sockmap attachments to UDP sockets, it simply won't work.
From Lorenz Bauer.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (83 commits)
net: ethernet: ti: ale: fix allmulti for nu type ale
net: ethernet: ti: am65-cpsw-nuss: fix ale parameters init
net: atm: Remove the error message according to the atomic context
bpf: Undo internal BPF_PROBE_MEM in BPF insns dump
libbpf: Support pre-initializing .bss global variables
tools/bpftool: Fix skeleton codegen
bpf: Fix memlock accounting for sock_hash
bpf: sockmap: Don't attach programs to UDP sockets
bpf: tcp: Recv() should return 0 when the peer socket is closed
ibmvnic: Flush existing work items before device removal
genetlink: clean up family attributes allocations
net: ipa: header pad field only valid for AP->modem endpoint
net: ipa: program upper nibbles of sequencer type
net: ipa: fix modem LAN RX endpoint id
net: ipa: program metadata mask differently
ionic: add pcie_print_link_status
rxrpc: Fix race between incoming ACK parser and retransmitter
net/mlx5: E-Switch, Fix some error pointer dereferences
net/mlx5: Don't fail driver on failure to create debugfs
net/mlx5e: CT: Fix ipv6 nat header rewrite actions
...
|
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David S. Miller
|
fa7566a0d6 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Alexei Starovoitov says: ==================== pull-request: bpf 2020-06-12 The following pull-request contains BPF updates for your *net* tree. We've added 26 non-merge commits during the last 10 day(s) which contain a total of 27 files changed, 348 insertions(+), 93 deletions(-). The main changes are: 1) sock_hash accounting fix, from Andrey. 2) libbpf fix and probe_mem sanitizing, from Andrii. 3) sock_hash fixes, from Jakub. 4) devmap_val fix, from Jesper. 5) load_bytes_relative fix, from YiFei. ==================== Signed-off-by: David S. Miller <davem@davemloft.net> |
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|
Linus Torvalds
|
6adc19fd13 |
Kbuild updates for v5.8 (2nd)
- fix build rules in binderfs sample - fix build errors when Kbuild recurses to the top Makefile - covert '---help---' in Kconfig to 'help' -----BEGIN PGP SIGNATURE----- iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl7lBuYVHG1hc2FoaXJv eUBrZXJuZWwub3JnAAoJED2LAQed4NsGHvIP/3iErjPshpg/phwH8NTCS4SFkiti BZRM+2lupSn7Qs53BTpVzIkXoHBJQZlJxlQ5HY8ScO+fiz28rKZr+b40us+je1Q+ SkvSPfwZzxjEg7lAZutznG4KgItJLWJKmDyh9T8Y8TAuG4f8WO0hKnXoAp3YorS2 zppEIxso8O5spZPjp+fF/fPbxPjIsabGK7Jp2LpSVFR5pVDHI/ycTlKQS+MFpMEx 6JIpdFRw7TkvKew1dr5uAWT5btWHatEqjSR3JeyVHv3EICTGQwHmcHK67cJzGInK T51+DT7/CpKtmRgGMiTEu/INfMzzoQAKl6Fcu+vMaShTN97Hk9DpdtQyvA6P/h3L 8GA4UBct05J7fjjIB7iUD+GYQ0EZbaFujzRXLYk+dQqEJRbhcCwvdzggGp0WvGRs 1f8/AIpgnQv8JSL/bOMgGMS5uL2dSLsgbzTdr6RzWf1jlYdI1i4u7AZ/nBrwWP+Z iOBkKsVceEoJrTbaynl3eoYqFLtWyDau+//oBc2gUvmhn8ioM5dfqBRiJjxJnPG9 /giRj6xRIqMMEw8Gg8PCG7WebfWxWyaIQwlWBbPok7DwISURK5mvOyakZL+Q25/y 6MBr2H8NEJsf35q0GTINpfZnot7NX4JXrrndJH8NIRC7HEhwd29S041xlQJdP0rs E76xsOr3hrAmBu4P =1NIT -----END PGP SIGNATURE----- Merge tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - fix build rules in binderfs sample - fix build errors when Kbuild recurses to the top Makefile - covert '---help---' in Kconfig to 'help' * tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: treewide: replace '---help---' in Kconfig files with 'help' kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables samples: binderfs: really compile this sample and fix build issues |
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|
Linus Torvalds
|
076f14be7f |
The X86 entry, exception and interrupt code rework
This all started about 6 month ago with the attempt to move the Posix CPU timer heavy lifting out of the timer interrupt code and just have lockless quick checks in that code path. Trivial 5 patches. This unearthed an inconsistency in the KVM handling of task work and the review requested to move all of this into generic code so other architectures can share. Valid request and solved with another 25 patches but those unearthed inconsistencies vs. RCU and instrumentation. Digging into this made it obvious that there are quite some inconsistencies vs. instrumentation in general. The int3 text poke handling in particular was completely unprotected and with the batched update of trace events even more likely to expose to endless int3 recursion. In parallel the RCU implications of instrumenting fragile entry code came up in several discussions. The conclusion of the X86 maintainer team was to go all the way and make the protection against any form of instrumentation of fragile and dangerous code pathes enforcable and verifiable by tooling. A first batch of preparatory work hit mainline with commit |
||
Masahiro Yamada
|
a7f7f6248d |
treewide: replace '---help---' in Kconfig files with 'help'
Since commit
|
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|
Linus Torvalds
|
6c32978414 |
Notifications over pipes + Keyring notifications
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Merge tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull notification queue from David Howells:
"This adds a general notification queue concept and adds an event
source for keys/keyrings, such as linking and unlinking keys and
changing their attributes.
Thanks to Debarshi Ray, we do have a pull request to use this to fix a
problem with gnome-online-accounts - as mentioned last time:
https://gitlab.gnome.org/GNOME/gnome-online-accounts/merge_requests/47
Without this, g-o-a has to constantly poll a keyring-based kerberos
cache to find out if kinit has changed anything.
[ There are other notification pending: mount/sb fsinfo notifications
for libmount that Karel Zak and Ian Kent have been working on, and
Christian Brauner would like to use them in lxc, but let's see how
this one works first ]
LSM hooks are included:
- A set of hooks are provided that allow an LSM to rule on whether or
not a watch may be set. Each of these hooks takes a different
"watched object" parameter, so they're not really shareable. The
LSM should use current's credentials. [Wanted by SELinux & Smack]
- A hook is provided to allow an LSM to rule on whether or not a
particular message may be posted to a particular queue. This is
given the credentials from the event generator (which may be the
system) and the watch setter. [Wanted by Smack]
I've provided SELinux and Smack with implementations of some of these
hooks.
WHY
===
Key/keyring notifications are desirable because if you have your
kerberos tickets in a file/directory, your Gnome desktop will monitor
that using something like fanotify and tell you if your credentials
cache changes.
However, we also have the ability to cache your kerberos tickets in
the session, user or persistent keyring so that it isn't left around
on disk across a reboot or logout. Keyrings, however, cannot currently
be monitored asynchronously, so the desktop has to poll for it - not
so good on a laptop. This facility will allow the desktop to avoid the
need to poll.
DESIGN DECISIONS
================
- The notification queue is built on top of a standard pipe. Messages
are effectively spliced in. The pipe is opened with a special flag:
pipe2(fds, O_NOTIFICATION_PIPE);
The special flag has the same value as O_EXCL (which doesn't seem
like it will ever be applicable in this context)[?]. It is given up
front to make it a lot easier to prohibit splice&co from accessing
the pipe.
[?] Should this be done some other way? I'd rather not use up a new
O_* flag if I can avoid it - should I add a pipe3() system call
instead?
The pipe is then configured::
ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, queue_depth);
ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &filter);
Messages are then read out of the pipe using read().
- It should be possible to allow write() to insert data into the
notification pipes too, but this is currently disabled as the
kernel has to be able to insert messages into the pipe *without*
holding pipe->mutex and the code to make this work needs careful
auditing.
- sendfile(), splice() and vmsplice() are disabled on notification
pipes because of the pipe->mutex issue and also because they
sometimes want to revert what they just did - but one or more
notification messages might've been interleaved in the ring.
- The kernel inserts messages with the wait queue spinlock held. This
means that pipe_read() and pipe_write() have to take the spinlock
to update the queue pointers.
- Records in the buffer are binary, typed and have a length so that
they can be of varying size.
This allows multiple heterogeneous sources to share a common
buffer; there are 16 million types available, of which I've used
just a few, so there is scope for others to be used. Tags may be
specified when a watchpoint is created to help distinguish the
sources.
- Records are filterable as types have up to 256 subtypes that can be
individually filtered. Other filtration is also available.
- Notification pipes don't interfere with each other; each may be
bound to a different set of watches. Any particular notification
will be copied to all the queues that are currently watching for it
- and only those that are watching for it.
- When recording a notification, the kernel will not sleep, but will
rather mark a queue as having lost a message if there's
insufficient space. read() will fabricate a loss notification
message at an appropriate point later.
- The notification pipe is created and then watchpoints are attached
to it, using one of:
keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01);
watch_mount(AT_FDCWD, "/", 0, fd, 0x02);
watch_sb(AT_FDCWD, "/mnt", 0, fd, 0x03);
where in both cases, fd indicates the queue and the number after is
a tag between 0 and 255.
- Watches are removed if either the notification pipe is destroyed or
the watched object is destroyed. In the latter case, a message will
be generated indicating the enforced watch removal.
Things I want to avoid:
- Introducing features that make the core VFS dependent on the
network stack or networking namespaces (ie. usage of netlink).
- Dumping all this stuff into dmesg and having a daemon that sits
there parsing the output and distributing it as this then puts the
responsibility for security into userspace and makes handling
namespaces tricky. Further, dmesg might not exist or might be
inaccessible inside a container.
- Letting users see events they shouldn't be able to see.
TESTING AND MANPAGES
====================
- The keyutils tree has a pipe-watch branch that has keyctl commands
for making use of notifications. Proposed manual pages can also be
found on this branch, though a couple of them really need to go to
the main manpages repository instead.
If the kernel supports the watching of keys, then running "make
test" on that branch will cause the testing infrastructure to spawn
a monitoring process on the side that monitors a notifications pipe
for all the key/keyring changes induced by the tests and they'll
all be checked off to make sure they happened.
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/log/?h=pipe-watch
- A test program is provided (samples/watch_queue/watch_test) that
can be used to monitor for keyrings, mount and superblock events.
Information on the notifications is simply logged to stdout"
* tag 'notifications-20200601' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
smack: Implement the watch_key and post_notification hooks
selinux: Implement the watch_key security hook
keys: Make the KEY_NEED_* perms an enum rather than a mask
pipe: Add notification lossage handling
pipe: Allow buffers to be marked read-whole-or-error for notifications
Add sample notification program
watch_queue: Add a key/keyring notification facility
security: Add hooks to rule on setting a watch
pipe: Add general notification queue support
pipe: Add O_NOTIFICATION_PIPE
security: Add a hook for the point of notification insertion
uapi: General notification queue definitions
|
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Andrii Nakryiko
|
29fcb05bbf |
bpf: Undo internal BPF_PROBE_MEM in BPF insns dump
BPF_PROBE_MEM is kernel-internal implmementation details. When dumping BPF
instructions to user-space, it needs to be replaced back with BPF_MEM mode.
Fixes:
|
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|
Linus Torvalds
|
5c2fb57af0 |
One more printk change for 5.8
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|
Linus Torvalds
|
b791d1bdf9 |
The Kernel Concurrency Sanitizer (KCSAN)
KCSAN is a dynamic race detector, which relies on compile-time instrumentation, and uses a watchpoint-based sampling approach to detect races. The feature was under development for quite some time and has already found legitimate bugs. Unfortunately it comes with a limitation, which was only understood late in the development cycle: It requires an up to date CLANG-11 compiler CLANG-11 is not yet released (scheduled for June), but it's the only compiler today which handles the kernel requirements and especially the annotations of functions to exclude them from KCSAN instrumentation correctly. These annotations really need to work so that low level entry code and especially int3 text poke handling can be completely isolated. A detailed discussion of the requirements and compiler issues can be found here: https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/ We came to the conclusion that trying to work around compiler limitations and bugs again would end up in a major trainwreck, so requiring a working compiler seemed to be the best choice. For Continous Integration purposes the compiler restriction is manageable and that's where most xxSAN reports come from. For a change this limitation might make GCC people actually look at their bugs. Some issues with CSAN in GCC are 7 years old and one has been 'fixed' 3 years ago with a half baken solution which 'solved' the reported issue but not the underlying problem. The KCSAN developers also ponder to use a GCC plugin to become independent, but that's not something which will show up in a few days. Blocking KCSAN until wide spread compiler support is available is not a really good alternative because the continuous growth of lockless optimizations in the kernel demands proper tooling support. -----BEGIN PGP SIGNATURE----- iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl7im98THHRnbHhAbGlu dXRyb25peC5kZQAKCRCmGPVMDXSYoQ3xD/9+q87OmwnyoRTs6O3GDDbWZYoJGolh rctDOAYW8RSS73Fiw23z8hKlLl9tJCya6/X8Q9qoonB1YeIEPPRVj5HJWAMUNEIs YgjlZJFmh+mnbP/KQFctm3AWpoX8kqt3ncqj6zG72oQ9qKui691BY/2NmGVSLxUV DqtUYSKmi51XEQtZuXRuHEf3zBxoyeD43DaSCdJAXd6f5O2X7tmrWDuazHVeKzHV lhijvkyBvGMWvPg0IBrXkkLmeOvS0++MTGm3o+L72XF6nWpzTkcV7N0E9GEDFg45 zwcidRVKD5d/1DoU5Tos96rCJpBEGh/wimlu0z14mcZpNiJgRQH5rzVEO9Y14UcP KL9FgRrb5dFw7yfX2zRQ070OFJ4AEDBMK0o5Lbu/QO5KLkvFkqnuWlQfmmtZJWCW DTRw/FgUgU7lvyPjRrao6HBvwy+yTb0u9K5seCOTRkuepR9nPJs0710pFiBsNCfV RY3cyggNBipAzgBOgLxixnq9+rHt70ton6S8Gijxpvt0dGGfO8k0wuEhFtA4zKrQ 6HGK+pidxnoVdEgyQZhS+qzMMkyiUL0FXdaGJ2IX+/DC+Ij1UrUPjZBn7v25M0hQ ESkvxWKCn7snH4/NJsNxqCV1zyEc3zAW/WvLJUc9I7H8zPwtVvKWPrKEMzrJJ5bA aneySilbRxBFUg== =iplm -----END PGP SIGNATURE----- Merge tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull the Kernel Concurrency Sanitizer from Thomas Gleixner: "The Kernel Concurrency Sanitizer (KCSAN) is a dynamic race detector, which relies on compile-time instrumentation, and uses a watchpoint-based sampling approach to detect races. The feature was under development for quite some time and has already found legitimate bugs. Unfortunately it comes with a limitation, which was only understood late in the development cycle: It requires an up to date CLANG-11 compiler CLANG-11 is not yet released (scheduled for June), but it's the only compiler today which handles the kernel requirements and especially the annotations of functions to exclude them from KCSAN instrumentation correctly. These annotations really need to work so that low level entry code and especially int3 text poke handling can be completely isolated. A detailed discussion of the requirements and compiler issues can be found here: https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/ We came to the conclusion that trying to work around compiler limitations and bugs again would end up in a major trainwreck, so requiring a working compiler seemed to be the best choice. For Continous Integration purposes the compiler restriction is manageable and that's where most xxSAN reports come from. For a change this limitation might make GCC people actually look at their bugs. Some issues with CSAN in GCC are 7 years old and one has been 'fixed' 3 years ago with a half baken solution which 'solved' the reported issue but not the underlying problem. The KCSAN developers also ponder to use a GCC plugin to become independent, but that's not something which will show up in a few days. Blocking KCSAN until wide spread compiler support is available is not a really good alternative because the continuous growth of lockless optimizations in the kernel demands proper tooling support" * tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits) compiler_types.h, kasan: Use __SANITIZE_ADDRESS__ instead of CONFIG_KASAN to decide inlining compiler.h: Move function attributes to compiler_types.h compiler.h: Avoid nested statement expression in data_race() compiler.h: Remove data_race() and unnecessary checks from {READ,WRITE}_ONCE() kcsan: Update Documentation to change supported compilers kcsan: Remove 'noinline' from __no_kcsan_or_inline kcsan: Pass option tsan-instrument-read-before-write to Clang kcsan: Support distinguishing volatile accesses kcsan: Restrict supported compilers kcsan: Avoid inserting __tsan_func_entry/exit if possible ubsan, kcsan: Don't combine sanitizer with kcov on clang objtool, kcsan: Add kcsan_disable_current() and kcsan_enable_current_nowarn() kcsan: Add __kcsan_{enable,disable}_current() variants checkpatch: Warn about data_race() without comment kcsan: Use GFP_ATOMIC under spin lock Improve KCSAN documentation a bit kcsan: Make reporting aware of KCSAN tests kcsan: Fix function matching in report kcsan: Change data_race() to no longer require marking racing accesses kcsan: Move kcsan_{disable,enable}_current() to kcsan-checks.h ... |
||
|
Linus Torvalds
|
a58dfea297 |
block-5.8-2020-06-11
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Merge tag 'block-5.8-2020-06-11' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"Some followup fixes for this merge window. In particular:
- Seqcount write missing preemption disable for stats (Ahmed)
- blktrace fixes (Chaitanya)
- Redundant initializations (Colin)
- Various small NVMe fixes (Chaitanya, Christoph, Daniel, Max,
Niklas, Rikard)
- loop flag bug regression fix (Martijn)
- blk-mq tagging fixes (Christoph, Ming)"
* tag 'block-5.8-2020-06-11' of git://git.kernel.dk/linux-block:
umem: remove redundant initialization of variable ret
pktcdvd: remove redundant initialization of variable ret
nvmet: fail outstanding host posted AEN req
nvme-pci: use simple suspend when a HMB is enabled
nvme-fc: don't call nvme_cleanup_cmd() for AENs
nvmet-tcp: constify nvmet_tcp_ops
nvme-tcp: constify nvme_tcp_mq_ops and nvme_tcp_admin_mq_ops
nvme: do not call del_gendisk() on a disk that was never added
blk-mq: fix blk_mq_all_tag_iter
blk-mq: split out a __blk_mq_get_driver_tag helper
blktrace: fix endianness for blk_log_remap()
blktrace: fix endianness in get_pdu_int()
blktrace: use errno instead of bi_status
block: nr_sects_write(): Disable preemption on seqcount write
block: remove the error argument to the block_bio_complete tracepoint
loop: Fix wrong masking of status flags
block/bio-integrity: don't free 'buf' if bio_integrity_add_page() failed
|
||
|
Linus Torvalds
|
6a45a65888 |
A set of fixes and updates for x86:
- Unbreak paravirt VDSO clocks. While the VDSO code was moved into lib
for sharing a subtle check for the validity of paravirt clocks got
replaced. While the replacement works perfectly fine for bare metal as
the update of the VDSO clock mode is synchronous, it fails for paravirt
clocks because the hypervisor can invalidate them asynchronous. Bring
it back as an optional function so it does not inflict this on
architectures which are free of PV damage.
- Fix the jiffies to jiffies64 mapping on 64bit so it does not trigger
an ODR violation on newer compilers
- Three fixes for the SSBD and *IB* speculation mitigation maze to ensure
consistency, not disabling of some *IB* variants wrongly and to prevent
a rogue cross process shutdown of SSBD. All marked for stable.
- Add yet more CPU models to the splitlock detection capable list !@#%$!
- Bring the pr_info() back which tells that TSC deadline timer is enabled.
- Reboot quirk for MacBook6,1
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Merge tag 'x86-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull more x86 updates from Thomas Gleixner:
"A set of fixes and updates for x86:
- Unbreak paravirt VDSO clocks.
While the VDSO code was moved into lib for sharing a subtle check
for the validity of paravirt clocks got replaced. While the
replacement works perfectly fine for bare metal as the update of
the VDSO clock mode is synchronous, it fails for paravirt clocks
because the hypervisor can invalidate them asynchronously.
Bring it back as an optional function so it does not inflict this
on architectures which are free of PV damage.
- Fix the jiffies to jiffies64 mapping on 64bit so it does not
trigger an ODR violation on newer compilers
- Three fixes for the SSBD and *IB* speculation mitigation maze to
ensure consistency, not disabling of some *IB* variants wrongly and
to prevent a rogue cross process shutdown of SSBD. All marked for
stable.
- Add yet more CPU models to the splitlock detection capable list
!@#%$!
- Bring the pr_info() back which tells that TSC deadline timer is
enabled.
- Reboot quirk for MacBook6,1"
* tag 'x86-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vdso: Unbreak paravirt VDSO clocks
lib/vdso: Provide sanity check for cycles (again)
clocksource: Remove obsolete ifdef
x86_64: Fix jiffies ODR violation
x86/speculation: PR_SPEC_FORCE_DISABLE enforcement for indirect branches.
x86/speculation: Prevent rogue cross-process SSBD shutdown
x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.
x86/cpu: Add Sapphire Rapids CPU model number
x86/split_lock: Add Icelake microserver and Tigerlake CPU models
x86/apic: Make TSC deadline timer detection message visible
x86/reboot/quirks: Add MacBook6,1 reboot quirk
|
||
|
Linus Torvalds
|
623f6dc593 |
Merge branch 'akpm' (patches from Andrew)
Merge some more updates from Andrew Morton: - various hotfixes and minor things - hch's use_mm/unuse_mm clearnups Subsystems affected by this patch series: mm/hugetlb, scripts, kcov, lib, nilfs, checkpatch, lib, mm/debug, ocfs2, lib, misc. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: kernel: set USER_DS in kthread_use_mm kernel: better document the use_mm/unuse_mm API contract kernel: move use_mm/unuse_mm to kthread.c kernel: move use_mm/unuse_mm to kthread.c stacktrace: cleanup inconsistent variable type lib: test get_count_order/long in test_bitops.c mm: add comments on pglist_data zones ocfs2: fix spelling mistake and grammar mm/debug_vm_pgtable: fix kernel crash by checking for THP support lib: fix bitmap_parse() on 64-bit big endian archs checkpatch: correct check for kernel parameters doc nilfs2: fix null pointer dereference at nilfs_segctor_do_construct() lib/lz4/lz4_decompress.c: document deliberate use of `&' kcov: check kcov_softirq in kcov_remote_stop() scripts/spelling: add a few more typos khugepaged: selftests: fix timeout condition in wait_for_scan() |
||
|
Linus Torvalds
|
55d728b2b0 |
arm64 merge window fixes for -rc1
- Fix SCS debug check to report max stack usage in bytes as advertised - Fix typo: CONFIG_FTRACE_WITH_REGS => CONFIG_DYNAMIC_FTRACE_WITH_REGS - Fix incorrect mask in HiSilicon L3C perf PMU driver - Fix compat vDSO compilation under some toolchain configurations - Fix false UBSAN warning from ACPI IORT parsing code - Fix booting under bootloaders that ignore TEXT_OFFSET - Annotate debug initcall function with '__init' -----BEGIN PGP SIGNATURE----- iQFEBAABCgAuFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAl7iMe8QHHdpbGxAa2Vy bmVsLm9yZwAKCRC3rHDchMFjNIp5B/46kdFZ1M8VSsGxtZMzLVZBR4MWzjx1wBD3 Zzvcg5x0aLAvg+VephmQ5cBiQE78/KKISUdTKndevJ9feVhzz8kxbOhLB88o14+L Pk63p4jol8v7cJHiqcsBgSLR6MDAiY+4epsgeFA7WkO9cf529UIMO1ea2TCx0KbT tKniZghX5I485Fu2RHtZGLGBxQXqFBcDJUok3/IoZnp2SDyUxrzHPViFL9fHHzCb FNSEJijcoHfrIKiG4bPssKICmvbtcNysembDlJeyZ+5qJXqotty2M3OK+We7vPrg Ne5O/tQoeCt4lLuW40yEmpQzodNLG8D+isC6cFvspmPXSyHflSCz =EtmQ -----END PGP SIGNATURE----- Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "arm64 fixes that came in during the merge window. There will probably be more to come, but it doesn't seem like it's worth me sitting on these in the meantime. - Fix SCS debug check to report max stack usage in bytes as advertised - Fix typo: CONFIG_FTRACE_WITH_REGS => CONFIG_DYNAMIC_FTRACE_WITH_REGS - Fix incorrect mask in HiSilicon L3C perf PMU driver - Fix compat vDSO compilation under some toolchain configurations - Fix false UBSAN warning from ACPI IORT parsing code - Fix booting under bootloaders that ignore TEXT_OFFSET - Annotate debug initcall function with '__init'" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: warn on incorrect placement of the kernel by the bootloader arm64: acpi: fix UBSAN warning arm64: vdso32: add CONFIG_THUMB2_COMPAT_VDSO drivers/perf: hisi: Fix wrong value for all counters enable arm64: ftrace: Change CONFIG_FTRACE_WITH_REGS to CONFIG_DYNAMIC_FTRACE_WITH_REGS arm64: debug: mark a function as __init to save some memory scs: Report SCS usage in bytes rather than number of entries |
||
Marco Elver
|
75d75b7a4d |
kcsan: Support distinguishing volatile accesses
In the kernel, the "volatile" keyword is used in various concurrent
contexts, whether in low-level synchronization primitives or for
legacy reasons. If supported by the compiler, it will be assumed
that aligned volatile accesses up to sizeof(long long) (matching
compiletime_assert_rwonce_type()) are atomic.
Recent versions of Clang [1] (GCC tentative [2]) can instrument
volatile accesses differently. Add the option (required) to enable the
instrumentation, and provide the necessary runtime functions. None of
the updated compilers are widely available yet (Clang 11 will be the
first release to support the feature).
[1]
|
||
Thomas Gleixner
|
37d1a04b13 |
Rebase locking/kcsan to locking/urgent
Merge the state of the locking kcsan branch before the read/write_once() and the atomics modifications got merged. Squash the fallout of the rebase on top of the read/write once and atomic fallback work into the merge. The history of the original branch is preserved in tag locking-kcsan-2020-06-02. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
||
|
Linus Torvalds
|
c742b63473 |
Highlights:
- Keep nfsd clients from unnecessarily breaking their own delegations: Note this requires a small kthreadd addition, discussed at: https://lore.kernel.org/r/1588348912-24781-1-git-send-email-bfields@redhat.com The result is Tejun Heo's suggestion, and he was OK with this going through my tree. - Patch nfsd/clients/ to display filenames, and to fix byte-order when displaying stateid's. - fix a module loading/unloading bug, from Neil Brown. - A big series from Chuck Lever with RPC/RDMA and tracing improvements, and lay some groundwork for RPC-over-TLS. Note Stephen Rothwell spotted two conflicts in linux-next. Both should be straightforward: include/trace/events/sunrpc.h https://lore.kernel.org/r/20200529105917.50dfc40f@canb.auug.org.au net/sunrpc/svcsock.c https://lore.kernel.org/r/20200529131955.26c421db@canb.auug.org.au -----BEGIN PGP SIGNATURE----- iQJJBAABCAAzFiEEYtFWavXG9hZotryuJ5vNeUKO4b4FAl7iRYwVHGJmaWVsZHNA ZmllbGRzZXMub3JnAAoJECebzXlCjuG+yx8QALIfyz/ziPgjGBnNJGCW8BjWHz7+ rGI+1SP2EUpgJ0fGJc9MpGyYTa5T3pTgsENnIRtegyZDISg2OQ5GfifpkTz4U7vg QbWRihs/W9EhltVYhKvtLASAuSAJ8ETbDfLXVb2ncY7iO6JNvb22xwsgKZILmzm1 uG4qSszmBZzpMUUy51kKJYJZ3ysP+v14qOnyOXEoeEMuJYNK9FkQ9bSPZ6wTJNOn hvZBMbU7LzRyVIvp358mFHY+vwq5qBNkJfVrZBkURGn4OxWPbWDXzqOi0Zs1oBjA L+QODIbTLGkopu/rD0r1b872PDtket7p5zsD8MreeI1vJOlt3xwqdCGlicIeNATI b0RG7sqh+pNv0mvwLxSNTf3rO0EKW6tUySqCnQZUAXFGRH0nYM2TWze4HUr2zfWT EgRMwxHY/AZUStZBuCIHPJ6inWnKuxSUELMf2a9JHO1BJc/yClRgmwJGdthVwb9u GP6F3/maFu+9YOO6iROMsqtxDA+q5vch5IBzevNOOBDEQDKqENmogR/knl9DmAhF sr+FOa3O0u6S4tgXw/TU97JS/h1L2Hu6QVEwU2iVzWtlUUOFVMZQODJTB6Lts4Ka gKzYXWvCHN+LyETsN6q7uHFg9mtO7xO5vrrIgo72SuVCscDw/8iHkoOOFLief+GE O0fR0IYjW8U1Rkn2 =YEf0 -----END PGP SIGNATURE----- Merge tag 'nfsd-5.8' of git://linux-nfs.org/~bfields/linux Pull nfsd updates from Bruce Fields: "Highlights: - Keep nfsd clients from unnecessarily breaking their own delegations. Note this requires a small kthreadd addition. The result is Tejun Heo's suggestion (see link), and he was OK with this going through my tree. - Patch nfsd/clients/ to display filenames, and to fix byte-order when displaying stateid's. - fix a module loading/unloading bug, from Neil Brown. - A big series from Chuck Lever with RPC/RDMA and tracing improvements, and lay some groundwork for RPC-over-TLS" Link: https://lore.kernel.org/r/1588348912-24781-1-git-send-email-bfields@redhat.com * tag 'nfsd-5.8' of git://linux-nfs.org/~bfields/linux: (49 commits) sunrpc: use kmemdup_nul() in gssp_stringify() nfsd: safer handling of corrupted c_type nfsd4: make drc_slab global, not per-net SUNRPC: Remove unreachable error condition in rpcb_getport_async() nfsd: Fix svc_xprt refcnt leak when setup callback client failed sunrpc: clean up properly in gss_mech_unregister() sunrpc: svcauth_gss_register_pseudoflavor must reject duplicate registrations. sunrpc: check that domain table is empty at module unload. NFSD: Fix improperly-formatted Doxygen comments NFSD: Squash an annoying compiler warning SUNRPC: Clean up request deferral tracepoints NFSD: Add tracepoints for monitoring NFSD callbacks NFSD: Add tracepoints to the NFSD state management code NFSD: Add tracepoints to NFSD's duplicate reply cache SUNRPC: svc_show_status() macro should have enum definitions SUNRPC: Restructure svc_udp_recvfrom() SUNRPC: Refactor svc_recvfrom() SUNRPC: Clean up svc_release_skb() functions SUNRPC: Refactor recvfrom path dealing with incomplete TCP receives SUNRPC: Replace dprintk() call sites in TCP receive path ... |
||
Peter Zijlstra
|
6eebad1ad3 |
lockdep: __always_inline more for noinstr
vmlinux.o: warning: objtool: debug_locks_off()+0xd: call to __debug_locks_off() leaves .noinstr.text section vmlinux.o: warning: objtool: match_held_lock()+0x6a: call to look_up_lock_class.isra.0() leaves .noinstr.text section vmlinux.o: warning: objtool: lock_is_held_type()+0x90: call to lockdep_recursion_finish() leaves .noinstr.text section Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200603114052.185201076@infradead.org |
||
|
Peter Zijlstra
|
bf2b300844 |
x86/entry: Rename trace_hardirqs_off_prepare()
The typical pattern for trace_hardirqs_off_prepare() is:
ENTRY
lockdep_hardirqs_off(); // because hardware
... do entry magic
instrumentation_begin();
trace_hardirqs_off_prepare();
... do actual work
trace_hardirqs_on_prepare();
lockdep_hardirqs_on_prepare();
instrumentation_end();
... do exit magic
lockdep_hardirqs_on();
which shows that it's named wrong, rename it to
trace_hardirqs_off_finish(), as it concludes the hardirq_off transition.
Also, given that the above is the only correct order, make the traditional
all-in-one trace_hardirqs_off() follow suit.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200529213321.415774872@infradead.org
|
||
|
Peter Zijlstra
|
59bc300b71 |
x86/entry: Clarify irq_{enter,exit}_rcu()
Because: irq_enter_rcu() includes lockdep_hardirq_enter() irq_exit_rcu() does *NOT* include lockdep_hardirq_exit() Which resulted in two 'stray' lockdep_hardirq_exit() calls in idtentry.h, and me spending a long time trying to find the matching enter calls. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200529213321.359433429@infradead.org |
||
|
Thomas Gleixner
|
8a6bc4787f |
genirq: Provide irq_enter/exit_rcu()
irq_enter()/exit() currently include RCU handling. To properly separate the RCU handling code, provide variants which contain only the non-RCU related functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20200521202117.567023613@linutronix.de |
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Thomas Gleixner
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865d3a9afe |
x86/mce: Address objtools noinstr complaints
Mark the relevant functions noinstr, use the plain non-instrumented MSR accessors. The only odd part is the instrumentation_begin()/end() pair around the indirect machine_check_vector() call as objtool can't figure that out. The possible invoked functions are annotated correctly. Also use notrace variant of nmi_enter/exit(). If MCEs happen then hardware latency tracing is the least of the worries. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lkml.kernel.org/r/20200505135315.476734898@linutronix.de |
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Thomas Gleixner
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5916d5f9b3 |
bug: Annotate WARN/BUG/stackfail as noinstr safe
Warnings, bugs and stack protection fails from noinstr sections, e.g. low level and early entry code, are likely to be fatal. Mark them as "safe" to be invoked from noinstr protected code to avoid annotating all usage sites. Getting the information out is important. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134100.376598577@linutronix.de |
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Thomas Gleixner
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0372007f5a |
context_tracking: Ensure that the critical path cannot be instrumented
context tracking lacks a few protection mechanisms against instrumentation: - While the core functions are marked NOKPROBE they lack protection against function tracing which is required as the function entry/exit points can be utilized by BPF. - static functions invoked from the protected functions need to be marked as well as they can be instrumented otherwise. - using plain inline allows the compiler to emit traceable and probable functions. Fix this by marking the functions noinstr and converting the plain inlines to __always_inline. The NOKPROBE_SYMBOL() annotations are removed as the .noinstr.text section is already excluded from being probed. Cures the following objtool warnings: vmlinux.o: warning: objtool: enter_from_user_mode()+0x34: call to __context_tracking_exit() leaves .noinstr.text section vmlinux.o: warning: objtool: prepare_exit_to_usermode()+0x29: call to __context_tracking_enter() leaves .noinstr.text section vmlinux.o: warning: objtool: syscall_return_slowpath()+0x29: call to __context_tracking_enter() leaves .noinstr.text section vmlinux.o: warning: objtool: do_syscall_64()+0x7f: call to __context_tracking_enter() leaves .noinstr.text section vmlinux.o: warning: objtool: do_int80_syscall_32()+0x3d: call to __context_tracking_enter() leaves .noinstr.text section vmlinux.o: warning: objtool: do_fast_syscall_32()+0x9c: call to __context_tracking_enter() leaves .noinstr.text section and generates new ones... Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134340.811520478@linutronix.de |
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Petr Mladek
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2a9e5ded95 |
printk/kdb: Redirect printk messages into kdb in any context
kdb has to get messages on consoles even when the system is stopped. It uses kdb_printf() internally and calls console drivers on its own. It uses a hack to reuse an existing code. It sets "kdb_trap_printk" global variable to redirect even the normal printk() into the kdb_printf() variant. The variable "kdb_trap_printk" is checked in printk_default() and it is ignored when printk is redirected to printk_safe in NMI context. Solve this by moving the check into printk_func(). It is obvious that it is not fully safe. But it does not make things worse. The console drivers are already called in this context by db_printf() direct calls. Reported-by: Sumit Garg <sumit.garg@linaro.org> Tested-by: Sumit Garg <sumit.garg@linaro.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20200520102233.GC3464@linux-b0ei |
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Christoph Hellwig
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37c54f9bd4 |
kernel: set USER_DS in kthread_use_mm
Some architectures like arm64 and s390 require USER_DS to be set for kernel threads to access user address space, which is the whole purpose of kthread_use_mm, but other like x86 don't. That has lead to a huge mess where some callers are fixed up once they are tested on said architectures, while others linger around and yet other like io_uring try to do "clever" optimizations for what usually is just a trivial asignment to a member in the thread_struct for most architectures. Make kthread_use_mm set USER_DS, and kthread_unuse_mm restore to the previous value instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Michael S. Tsirkin <mst@redhat.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Felipe Balbi <balbi@kernel.org> Cc: Felix Kuehling <Felix.Kuehling@amd.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: http://lkml.kernel.org/r/20200404094101.672954-7-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Christoph Hellwig
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f5678e7f2a |
kernel: better document the use_mm/unuse_mm API contract
Switch the function documentation to kerneldoc comments, and add WARN_ON_ONCE asserts that the calling thread is a kernel thread and does not have ->mm set (or has ->mm set in the case of unuse_mm). Also give the functions a kthread_ prefix to better document the use case. [hch@lst.de: fix a comment typo, cover the newly merged use_mm/unuse_mm caller in vfio] Link: http://lkml.kernel.org/r/20200416053158.586887-3-hch@lst.de [sfr@canb.auug.org.au: powerpc/vas: fix up for {un}use_mm() rename] Link: http://lkml.kernel.org/r/20200422163935.5aa93ba5@canb.auug.org.au Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Tested-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [usb] Acked-by: Haren Myneni <haren@linux.ibm.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Felipe Balbi <balbi@kernel.org> Cc: Jason Wang <jasowang@redhat.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Link: http://lkml.kernel.org/r/20200404094101.672954-6-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |