Commit Graph

6416 Commits

Author SHA1 Message Date
Linus Torvalds ed016af52e These are the locking updates for v5.10:
- Add deadlock detection for recursive read-locks. The rationale is outlined
    in:
 
      224ec489d3cd: ("lockdep/Documention: Recursive read lock detection reasoning")
 
    The main deadlock pattern we want to detect is:
 
            TASK A:                 TASK B:
 
            read_lock(X);
                                    write_lock(X);
            read_lock_2(X);
 
  - Add "latch sequence counters" (seqcount_latch_t):
 
       A sequence counter variant where the counter even/odd value is used to
       switch between two copies of protected data. This allows the read path,
       typically NMIs, to safely interrupt the write side critical section.
 
    We utilize this new variant for sched-clock, and to make x86 TSC handling safer.
 
  - Other seqlock cleanups, fixes and enhancements
 
  - KCSAN updates
 
  - LKMM updates
 
  - Misc updates, cleanups and fixes.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
 "These are the locking updates for v5.10:

   - Add deadlock detection for recursive read-locks.

     The rationale is outlined in commit 224ec489d3 ("lockdep/
     Documention: Recursive read lock detection reasoning")

     The main deadlock pattern we want to detect is:

           TASK A:                 TASK B:

           read_lock(X);
                                   write_lock(X);
           read_lock_2(X);

   - Add "latch sequence counters" (seqcount_latch_t):

     A sequence counter variant where the counter even/odd value is used
     to switch between two copies of protected data. This allows the
     read path, typically NMIs, to safely interrupt the write side
     critical section.

     We utilize this new variant for sched-clock, and to make x86 TSC
     handling safer.

   - Other seqlock cleanups, fixes and enhancements

   - KCSAN updates

   - LKMM updates

   - Misc updates, cleanups and fixes"

* tag 'locking-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
  lockdep: Revert "lockdep: Use raw_cpu_*() for per-cpu variables"
  lockdep: Fix lockdep recursion
  lockdep: Fix usage_traceoverflow
  locking/atomics: Check atomic-arch-fallback.h too
  locking/seqlock: Tweak DEFINE_SEQLOCK() kernel doc
  lockdep: Optimize the memory usage of circular queue
  seqlock: Unbreak lockdep
  seqlock: PREEMPT_RT: Do not starve seqlock_t writers
  seqlock: seqcount_LOCKNAME_t: Introduce PREEMPT_RT support
  seqlock: seqcount_t: Implement all read APIs as statement expressions
  seqlock: Use unique prefix for seqcount_t property accessors
  seqlock: seqcount_LOCKNAME_t: Standardize naming convention
  seqlock: seqcount latch APIs: Only allow seqcount_latch_t
  rbtree_latch: Use seqcount_latch_t
  x86/tsc: Use seqcount_latch_t
  timekeeping: Use seqcount_latch_t
  time/sched_clock: Use seqcount_latch_t
  seqlock: Introduce seqcount_latch_t
  mm/swap: Do not abuse the seqcount_t latching API
  time/sched_clock: Use raw_read_seqcount_latch() during suspend
  ...
2020-10-12 13:06:20 -07:00
Linus Torvalds 20d49bfcc3 A small set of updates for debug objects:
- Make all debug object descriptors constant. There is no reason to have
    them writeable.
 
  - Free the per CPU object pool after CPU unplug to avoid memory waste.
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Merge tag 'core-debugobjects-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull debugobjects updates from Thomas Gleixner:
 "A small set of updates for debug objects:

   - Make all debug object descriptors constant. There is no reason to
     have them writeable.

   - Free the per CPU object pool after CPU unplug to avoid memory
     waste"

* tag 'core-debugobjects-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  debugobjects: Free per CPU pool after CPU unplug
  treewide: Make all debug_obj_descriptors const
  debugobjects: Allow debug_obj_descr to be const
2020-10-12 11:21:24 -07:00
Linus Torvalds ca1b66922a * Extend the recovery from MCE in kernel space also to processes which
encounter an MCE in kernel space but while copying from user memory by
 sending them a SIGBUS on return to user space and umapping the faulty
 memory, by Tony Luck and Youquan Song.
 
 * memcpy_mcsafe() rework by splitting the functionality into
 copy_mc_to_user() and copy_mc_to_kernel(). This, as a result, enables
 support for new hardware which can recover from a machine check
 encountered during a fast string copy and makes that the default and
 lets the older hardware which does not support that advance recovery,
 opt in to use the old, fragile, slow variant, by Dan Williams.
 
 * New AMD hw enablement, by Yazen Ghannam and Akshay Gupta.
 
 * Do not use MSR-tracing accessors in #MC context and flag any fault
 while accessing MCA architectural MSRs as an architectural violation
 with the hope that such hw/fw misdesigns are caught early during the hw
 eval phase and they don't make it into production.
 
 * Misc fixes, improvements and cleanups, as always.
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Merge tag 'ras_updates_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS updates from Borislav Petkov:

 - Extend the recovery from MCE in kernel space also to processes which
   encounter an MCE in kernel space but while copying from user memory
   by sending them a SIGBUS on return to user space and umapping the
   faulty memory, by Tony Luck and Youquan Song.

 - memcpy_mcsafe() rework by splitting the functionality into
   copy_mc_to_user() and copy_mc_to_kernel(). This, as a result, enables
   support for new hardware which can recover from a machine check
   encountered during a fast string copy and makes that the default and
   lets the older hardware which does not support that advance recovery,
   opt in to use the old, fragile, slow variant, by Dan Williams.

 - New AMD hw enablement, by Yazen Ghannam and Akshay Gupta.

 - Do not use MSR-tracing accessors in #MC context and flag any fault
   while accessing MCA architectural MSRs as an architectural violation
   with the hope that such hw/fw misdesigns are caught early during the
   hw eval phase and they don't make it into production.

 - Misc fixes, improvements and cleanups, as always.

* tag 'ras_updates_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Allow for copy_mc_fragile symbol checksum to be generated
  x86/mce: Decode a kernel instruction to determine if it is copying from user
  x86/mce: Recover from poison found while copying from user space
  x86/mce: Avoid tail copy when machine check terminated a copy from user
  x86/mce: Add _ASM_EXTABLE_CPY for copy user access
  x86/mce: Provide method to find out the type of an exception handler
  x86/mce: Pass pointer to saved pt_regs to severity calculation routines
  x86/copy_mc: Introduce copy_mc_enhanced_fast_string()
  x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()
  x86/mce: Drop AMD-specific "DEFERRED" case from Intel severity rule list
  x86/mce: Add Skylake quirk for patrol scrub reported errors
  RAS/CEC: Convert to DEFINE_SHOW_ATTRIBUTE()
  x86/mce: Annotate mce_rd/wrmsrl() with noinstr
  x86/mce/dev-mcelog: Do not update kflags on AMD systems
  x86/mce: Stop mce_reign() from re-computing severity for every CPU
  x86/mce: Make mce_rdmsrl() panic on an inaccessible MSR
  x86/mce: Increase maximum number of banks to 64
  x86/mce: Delay clearing IA32_MCG_STATUS to the end of do_machine_check()
  x86/MCE/AMD, EDAC/mce_amd: Remove struct smca_hwid.xec_bitmap
  RAS/CEC: Fix cec_init() prototype
2020-10-12 10:14:38 -07:00
Ingo Molnar d6c4c11348 Merge branch 'kcsan' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/core
Pull KCSAN updates for v5.10 from Paul E. McKenney:

 - Improve kernel messages.

 - Be more permissive with bitops races under KCSAN_ASSUME_PLAIN_WRITES_ATOMIC=y.

 - Optimize debugfs stat counters.

 - Introduce the instrument_*read_write() annotations, to provide a
   finer description of certain ops - using KCSAN's compound instrumentation.
   Use them for atomic RNW and bitops, where appropriate.
   Doing this might find new races.
   (Depends on the compiler having tsan-compound-read-before-write=1 support.)

 - Support atomic built-ins, which will help certain architectures, such as s390.

 - Misc enhancements and smaller fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-09 08:56:02 +02:00
Ingo Molnar e705d39796 Merge branch 'locking/urgent' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-10-09 08:55:17 +02:00
Dan Williams ec6347bb43 x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()
In reaction to a proposal to introduce a memcpy_mcsafe_fast()
implementation Linus points out that memcpy_mcsafe() is poorly named
relative to communicating the scope of the interface. Specifically what
addresses are valid to pass as source, destination, and what faults /
exceptions are handled.

Of particular concern is that even though x86 might be able to handle
the semantics of copy_mc_to_user() with its common copy_user_generic()
implementation other archs likely need / want an explicit path for this
case:

  On Fri, May 1, 2020 at 11:28 AM Linus Torvalds <torvalds@linux-foundation.org> wrote:
  >
  > On Thu, Apr 30, 2020 at 6:21 PM Dan Williams <dan.j.williams@intel.com> wrote:
  > >
  > > However now I see that copy_user_generic() works for the wrong reason.
  > > It works because the exception on the source address due to poison
  > > looks no different than a write fault on the user address to the
  > > caller, it's still just a short copy. So it makes copy_to_user() work
  > > for the wrong reason relative to the name.
  >
  > Right.
  >
  > And it won't work that way on other architectures. On x86, we have a
  > generic function that can take faults on either side, and we use it
  > for both cases (and for the "in_user" case too), but that's an
  > artifact of the architecture oddity.
  >
  > In fact, it's probably wrong even on x86 - because it can hide bugs -
  > but writing those things is painful enough that everybody prefers
  > having just one function.

Replace a single top-level memcpy_mcsafe() with either
copy_mc_to_user(), or copy_mc_to_kernel().

Introduce an x86 copy_mc_fragile() name as the rename for the
low-level x86 implementation formerly named memcpy_mcsafe(). It is used
as the slow / careful backend that is supplanted by a fast
copy_mc_generic() in a follow-on patch.

One side-effect of this reorganization is that separating copy_mc_64.S
to its own file means that perf no longer needs to track dependencies
for its memcpy_64.S benchmarks.

 [ bp: Massage a bit. ]

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: <stable@vger.kernel.org>
Link: http://lore.kernel.org/r/CAHk-=wjSqtXAqfUJxFtWNwmguFASTgB0dz1dT3V-78Quiezqbg@mail.gmail.com
Link: https://lkml.kernel.org/r/160195561680.2163339.11574962055305783722.stgit@dwillia2-desk3.amr.corp.intel.com
2020-10-06 11:18:04 +02:00
Dave Airlie 86fdf61e71 drm-misc-fixes for v5.9:
- Small doc fix.
 - Re-add FB_ARMCLCD for android.
 - Fix global-out-of-bounds read in fbcon_get_font().
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Merge tag 'drm-misc-fixes-2020-10-01' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

drm-misc-fixes for v5.9:
- Small doc fix.
- Re-add FB_ARMCLCD for android.
- Fix global-out-of-bounds read in fbcon_get_font().

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/8585daa2-fcbc-3924-ac4f-e7b5668808e0@linux.intel.com
2020-10-06 12:38:28 +10:00
Thibaut Sautereau 09a6b0bc3b random32: Restore __latent_entropy attribute on net_rand_state
Commit f227e3ec3b ("random32: update the net random state on interrupt
and activity") broke compilation and was temporarily fixed by Linus in
83bdc7275e ("random32: remove net_rand_state from the latent entropy
gcc plugin") by entirely moving net_rand_state out of the things handled
by the latent_entropy GCC plugin.

From what I understand when reading the plugin code, using the
__latent_entropy attribute on a declaration was the wrong part and
simply keeping the __latent_entropy attribute on the variable definition
was the correct fix.

Fixes: 83bdc7275e ("random32: remove net_rand_state from the latent entropy gcc plugin")
Acked-by: Willy Tarreau <w@1wt.eu>
Cc: Emese Revfy <re.emese@gmail.com>
Signed-off-by: Thibaut Sautereau <thibaut.sautereau@ssi.gouv.fr>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-02 09:31:54 -07:00
Zqiang 88451f2cd3 debugobjects: Free per CPU pool after CPU unplug
If a CPU is offlined the debug objects per CPU pool is not cleaned up. If
the CPU is never onlined again then the objects in the pool are wasted.

Add a CPU hotplug callback which is invoked after the CPU is dead to free
the pool.

[ tglx: Massaged changelog and added comment about remote access safety ]

Signed-off-by: Zqiang <qiang.zhang@windriver.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/20200908062709.11441-1-qiang.zhang@windriver.com
2020-10-01 16:13:54 +02:00
Jason Yan ffa550cd69 lib/memregion.c: include memregion.h
This addresses the following sparse warning:

  lib/memregion.c:8:5: warning: symbol 'memregion_alloc' was not declared. Should it be static?
  lib/memregion.c:14:6: warning: symbol 'memregion_free' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/20200921142852.875312-1-yanaijie@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-26 10:33:57 -07:00
Nick Desaulniers 1e1b6d63d6 lib/string.c: implement stpcpy
LLVM implemented a recent "libcall optimization" that lowers calls to
`sprintf(dest, "%s", str)` where the return value is used to
`stpcpy(dest, str) - dest`.

This generally avoids the machinery involved in parsing format strings.
`stpcpy` is just like `strcpy` except it returns the pointer to the new
tail of `dest`.  This optimization was introduced into clang-12.

Implement this so that we don't observe linkage failures due to missing
symbol definitions for `stpcpy`.

Similar to last year's fire drill with: commit 5f074f3e19
("lib/string.c: implement a basic bcmp")

The kernel is somewhere between a "freestanding" environment (no full
libc) and "hosted" environment (many symbols from libc exist with the
same type, function signature, and semantics).

As Peter Anvin notes, there's not really a great way to inform the
compiler that you're targeting a freestanding environment but would like
to opt-in to some libcall optimizations (see pr/47280 below), rather
than opt-out.

Arvind notes, -fno-builtin-* behaves slightly differently between GCC
and Clang, and Clang is missing many __builtin_* definitions, which I
consider a bug in Clang and am working on fixing.

Masahiro summarizes the subtle distinction between compilers justly:
  To prevent transformation from foo() into bar(), there are two ways in
  Clang to do that; -fno-builtin-foo, and -fno-builtin-bar.  There is
  only one in GCC; -fno-buitin-foo.

(Any difference in that behavior in Clang is likely a bug from a missing
__builtin_* definition.)

Masahiro also notes:
  We want to disable optimization from foo() to bar(),
  but we may still benefit from the optimization from
  foo() into something else. If GCC implements the same transform, we
  would run into a problem because it is not -fno-builtin-bar, but
  -fno-builtin-foo that disables that optimization.

  In this regard, -fno-builtin-foo would be more future-proof than
  -fno-built-bar, but -fno-builtin-foo is still potentially overkill. We
  may want to prevent calls from foo() being optimized into calls to
  bar(), but we still may want other optimization on calls to foo().

It seems that compilers today don't quite provide the fine grain control
over which libcall optimizations pseudo-freestanding environments would
prefer.

Finally, Kees notes that this interface is unsafe, so we should not
encourage its use.  As such, I've removed the declaration from any
header, but it still needs to be exported to avoid linkage errors in
modules.

Reported-by: Sami Tolvanen <samitolvanen@google.com>
Suggested-by: Andy Lavr <andy.lavr@gmail.com>
Suggested-by: Arvind Sankar <nivedita@alum.mit.edu>
Suggested-by: Joe Perches <joe@perches.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200914161643.938408-1-ndesaulniers@google.com
Link: https://bugs.llvm.org/show_bug.cgi?id=47162
Link: https://bugs.llvm.org/show_bug.cgi?id=47280
Link: https://github.com/ClangBuiltLinux/linux/issues/1126
Link: https://man7.org/linux/man-pages/man3/stpcpy.3.html
Link: https://pubs.opengroup.org/onlinepubs/9699919799/functions/stpcpy.html
Link: https://reviews.llvm.org/D85963
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-26 10:33:57 -07:00
Peilin Ye 6735b4632d Fonts: Support FONT_EXTRA_WORDS macros for built-in fonts
syzbot has reported an issue in the framebuffer layer, where a malicious
user may overflow our built-in font data buffers.

In order to perform a reliable range check, subsystems need to know
`FONTDATAMAX` for each built-in font. Unfortunately, our font descriptor,
`struct console_font` does not contain `FONTDATAMAX`, and is part of the
UAPI, making it infeasible to modify it.

For user-provided fonts, the framebuffer layer resolves this issue by
reserving four extra words at the beginning of data buffers. Later,
whenever a function needs to access them, it simply uses the following
macros:

Recently we have gathered all the above macros to <linux/font.h>. Let us
do the same thing for built-in fonts, prepend four extra words (including
`FONTDATAMAX`) to their data buffers, so that subsystems can use these
macros for all fonts, no matter built-in or user-provided.

This patch depends on patch "fbdev, newport_con: Move FONT_EXTRA_WORDS
macros into linux/font.h".

Cc: stable@vger.kernel.org
Link: https://syzkaller.appspot.com/bug?id=08b8be45afea11888776f897895aef9ad1c3ecfd
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/ef18af00c35fb3cc826048a5f70924ed6ddce95b.1600953813.git.yepeilin.cs@gmail.com
2020-09-25 10:28:51 +02:00
Stephen Boyd f9e62f318f treewide: Make all debug_obj_descriptors const
This should make it harder for the kernel to corrupt the debug object
descriptor, used to call functions to fixup state and track debug objects,
by moving the structure to read-only memory.

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200815004027.2046113-3-swboyd@chromium.org
2020-09-24 21:56:25 +02:00
Stephen Boyd aedcade6f4 debugobjects: Allow debug_obj_descr to be const
The debugobject core could be slightly harder to corrupt if the
debug_obj_descr would be a pointer to const memory.

Depending on the architecture, const data structures are placed into
read-only memory and thus are harder to corrupt or hijack.

This descriptor is used to fix up stuff like timers and workqueues when
core kernel data structures are busted, so moving the descriptors to
read-only memory will make debugobjects more resilient to something going
wrong and then corrupting the function pointers inside struct
debug_obj_descr.

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200815004027.2046113-2-swboyd@chromium.org
2020-09-24 21:56:24 +02:00
Linus Torvalds c9c9e6a49f A couple of fixes for bootconfig
Masami discovered two bugs which this fixes and he added tests to
 cover these issues.
 
 - Fix a bug that breaks bootconfig tree nodes
 
 - Fix a bug that does not truncate whitespace properly
 
 - Add tests to cover the above two cases
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Merge tag 'trace-v5.9-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull bootconfig fixes from Steven Rostedt:
 "A couple of fixes for bootconfig.

  Masami discovered two bugs which this fixes and he added tests to
  cover these issues.

   - Fix a bug that breaks bootconfig tree nodes

   - Fix a bug that does not truncate whitespace properly

   - Add tests to cover the above two cases"

* tag 'trace-v5.9-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tools/bootconfig: Add testcase for tailing space
  tools/bootconfig: Add testcases for repeated key with brace
  lib/bootconfig: Fix to remove tailing spaces after value
  lib/bootconfig: Fix a bug of breaking existing tree nodes
2020-09-23 14:52:22 -07:00
Linus Torvalds d3017135c4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:

 - fix failure to add bond interfaces to a bridge, the offload-handling
   code was too defensive there and recent refactoring unearthed that.
   Users complained (Ido)

 - fix unnecessarily reflecting ECN bits within TOS values / QoS marking
   in TCP ACK and reset packets (Wei)

 - fix a deadlock with bpf iterator. Hopefully we're in the clear on
   this front now... (Yonghong)

 - BPF fix for clobbering r2 in bpf_gen_ld_abs (Daniel)

 - fix AQL on mt76 devices with FW rate control and add a couple of AQL
   issues in mac80211 code (Felix)

 - fix authentication issue with mwifiex (Maximilian)

 - WiFi connectivity fix: revert IGTK support in ti/wlcore (Mauro)

 - fix exception handling for multipath routes via same device (David
   Ahern)

 - revert back to a BH spin lock flavor for nsid_lock: there are paths
   which do require the BH context protection (Taehee)

 - fix interrupt / queue / NAPI handling in the lantiq driver (Hauke)

 - fix ife module load deadlock (Cong)

 - make an adjustment to netlink reply message type for code added in
   this release (the sole change touching uAPI here) (Michal)

 - a number of fixes for small NXP and Microchip switches (Vladimir)

[ Pull request acked by David: "you can expect more of this in the
  future as I try to delegate more things to Jakub" ]

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (167 commits)
  net: mscc: ocelot: fix some key offsets for IP4_TCP_UDP VCAP IS2 entries
  net: dsa: seville: fix some key offsets for IP4_TCP_UDP VCAP IS2 entries
  net: dsa: felix: fix some key offsets for IP4_TCP_UDP VCAP IS2 entries
  inet_diag: validate INET_DIAG_REQ_PROTOCOL attribute
  net: bridge: br_vlan_get_pvid_rcu() should dereference the VLAN group under RCU
  net: Update MAINTAINERS for MediaTek switch driver
  net/mlx5e: mlx5e_fec_in_caps() returns a boolean
  net/mlx5e: kTLS, Avoid kzalloc(GFP_KERNEL) under spinlock
  net/mlx5e: kTLS, Fix leak on resync error flow
  net/mlx5e: kTLS, Add missing dma_unmap in RX resync
  net/mlx5e: kTLS, Fix napi sync and possible use-after-free
  net/mlx5e: TLS, Do not expose FPGA TLS counter if not supported
  net/mlx5e: Fix using wrong stats_grps in mlx5e_update_ndo_stats()
  net/mlx5e: Fix multicast counter not up-to-date in "ip -s"
  net/mlx5e: Fix endianness when calculating pedit mask first bit
  net/mlx5e: Enable adding peer miss rules only if merged eswitch is supported
  net/mlx5e: CT: Fix freeing ct_label mapping
  net/mlx5e: Fix memory leak of tunnel info when rule under multipath not ready
  net/mlx5e: Use synchronize_rcu to sync with NAPI
  net/mlx5e: Use RCU to protect rq->xdp_prog
  ...
2020-09-22 14:43:50 -07:00
Masami Hiramatsu c7af4ecdff lib/bootconfig: Fix to remove tailing spaces after value
Fix to remove tailing spaces after value. If there is a space
after value, the bootconfig failed to remove it because it
applies strim() before replacing the delimiter with null.

For example,

foo = var    # comment

was parsed as below.

foo="var    "

but user will expect

foo="var"

This fixes it by applying strim() after removing the delimiter.

Link: https://lkml.kernel.org/r/160068149134.1088739.8868306567670058853.stgit@devnote2

Fixes: 76db5a27a8 ("bootconfig: Add Extra Boot Config support")
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21 21:50:09 -04:00
Masami Hiramatsu ead1e19ad9 lib/bootconfig: Fix a bug of breaking existing tree nodes
Fix a bug of breaking existing tree nodes by parsing the second
and subsequent braces. Since the bootconfig parser uses the
node.next field as a flag of current parent node, but this will
break the existing tree if the same key node is specified again
in the bootconfig.

For example, the following bootconfig should be foo.buz and bar.

foo
bar
foo { buz }

However, when parsing the brace "{", it breaks foo->bar link
by marking open-brace node. So the bootconfig unlinks bar
from the bootconfig internal tree.

This introduces a stack outside of the tree and record the
last open-brace on the stack instead of using node.next field.

Link: https://lkml.kernel.org/r/160068148267.1088739.8264704338030168660.stgit@devnote2

Fixes: 76db5a27a8 ("bootconfig: Add Extra Boot Config support")
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21 21:45:52 -04:00
Colin Ian King 769f5083c5 rhashtable: fix indentation of a continue statement
A continue statement is indented incorrectly, add in the missing
tab.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-20 14:10:06 -07:00
Changbin Du 2645d43205 kcsan: kconfig: move to menu 'Generic Kernel Debugging Instruments'
This moves the KCSAN kconfig items under menu 'Generic Kernel Debugging
Instruments' where UBSAN resides.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200904152224.5570-1-changbin.du@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-19 13:13:39 -07:00
Linus Torvalds 20a7b6be05 Driver core fixes for 5.9-rc5
Here are some small driver core and debugfs fixes for 5.9-rc5
 
 Included in here are:
 	- firmware loader memory leak fix
 	- firmware loader testing fixes for non-EFI systems
 	- device link locking fixes found by lockdep
 	- kobject_del() bugfix that has been affecting some callers
 	- debugfs minor fix
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are some small driver core and debugfs fixes for 5.9-rc5

  Included in here are:

   - firmware loader memory leak fix

   - firmware loader testing fixes for non-EFI systems

   - device link locking fixes found by lockdep

   - kobject_del() bugfix that has been affecting some callers

   - debugfs minor fix

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  test_firmware: Test platform fw loading on non-EFI systems
  PM: <linux/device.h>: fix @em_pd kernel-doc warning
  kobject: Drop unneeded conditional in __kobject_del()
  driver core: Fix device_pm_lock() locking for device links
  MAINTAINERS: Add the security document to SECURITY CONTACT
  driver code: print symbolic error code
  debugfs: Fix module state check condition
  kobject: Restore old behaviour of kobject_del(NULL)
  firmware_loader: fix memory leak for paged buffer
2020-09-13 09:02:59 -07:00
Greg Kroah-Hartman 952e934d7f Revert "dyndbg: accept query terms like file=bar and module=foo"
This reverts commit 14775b0496 as there
were still some parsing problems with it, and the follow-on patch for
it.

Let's revisit it later, just drop it for now.

Cc: <jbaron@akamai.com>
Cc: Jim Cromie <jim.cromie@gmail.com>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 14775b0496 ("dyndbg: accept query terms like file=bar and module=foo")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-10 18:45:03 +02:00
Greg Kroah-Hartman 7f6e1f3072 Revert "dyndbg: fix problem parsing format="foo bar""
This reverts commit 42f07816ac as it
still causes problems.  It will be resolved later, let's revert it so we
can also revert the original patch this was supposed to be helping with.

Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: 42f07816ac ("dyndbg: fix problem parsing format="foo bar"")
Cc: Jim Cromie <jim.cromie@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-10 18:42:38 +02:00
Kees Cook baaabecfc8 test_firmware: Test platform fw loading on non-EFI systems
On non-EFI systems, it wasn't possible to test the platform firmware
loader because it will have never set "checked_fw" during __init.
Instead, allow the test code to override this check. Additionally split
the declarations into a private symbol namespace so there is greater
enforcement of the symbol visibility.

Fixes: 548193cba2 ("test_firmware: add support for firmware_request_platform")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20200909225354.3118328-1-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-10 18:19:16 +02:00
Andy Shevchenko 07ecc6693f kobject: Drop unneeded conditional in __kobject_del()
__kobject_del() is called from two places, in one where kobj is dereferenced
before and thus can't be NULL, and in the other the NULL check is done before
call. Drop unneeded conditional in __kobject_del().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20200803083520.5460-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-07 11:24:17 +02:00
Jim Cromie 42f07816ac dyndbg: fix problem parsing format="foo bar"
commit 14775b0496 ("dyndbg: accept query terms like file=bar and
module=foo") added the combined keyword=value parsing poorly; revert
most of it, keeping the keyword & arg change.

Instead, fix the tokenizer for the new input, by terminating the
keyword (an unquoted word) on '=' as well as space, thus letting the
tokenizer work on the quoted argument, like it would have previously.

Also add a few debug-prints to show more parsing context, into
tokenizer and parse-query, and use "keyword, value" in others.

Fixes: 14775b0496 ("dyndbg: accept query terms like file=bar and module=foo")
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20200831182210.850852-4-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04 17:21:56 +02:00
Jim Cromie a2d375eda7 dyndbg: refine export, rename to dynamic_debug_exec_queries()
commit 4c0d77828d ("dyndbg: export ddebug_exec_queries") had a few
problems:
 - broken non DYNAMIC_DEBUG_CORE configs, sparse warning
 - the exported function modifies query string, breaks on RO strings.
 - func name follows internal convention, shouldn't be exposed as is.

1st is fixed in header with ifdefd function prototype or stub defn.
Also remove an obsolete HAVE-symbol ifdef-comment, and add others.

Fix others by wrapping existing internal function with a new one,
named in accordance with module-prefix naming convention, before
export hits v5.9.0.  In new function, copy query string to a local
buffer, so users can pass hard-coded/RO queries, and internal function
can be used unchanged.

Fixes: 4c0d77828d ("dyndbg: export ddebug_exec_queries")
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20200831182210.850852-3-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04 17:21:56 +02:00
Jim Cromie b52a95eac1 dyndbg: give %3u width in pr-format, cosmetic only
Specify the print-width so log entries line up nicely.

no functional changes.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20200831182210.850852-2-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04 17:21:56 +02:00
Andy Shevchenko 40b8b826a6 kobject: Restore old behaviour of kobject_del(NULL)
The commit 079ad2fb4b ("kobject: Avoid premature parent object freeing in
kobject_cleanup()") inadvertently dropped a possibility to call kobject_del()
with NULL pointer. Restore the old behaviour.

Fixes: 079ad2fb4b ("kobject: Avoid premature parent object freeing in kobject_cleanup()")
Cc: stable <stable@vger.kernel.org>
Reported-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Link: https://lore.kernel.org/r/20200803082706.65347-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-28 12:32:52 +02:00
Boqun Feng 96a16f45ae lockdep/selftest: Introduce recursion3
Add a test case shows that USED_IN_*_READ and ENABLE_*_READ can cause
deadlock too.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-20-boqun.feng@gmail.com
2020-08-26 12:42:08 +02:00
Boqun Feng ad56450db8 locking/selftest: Add test cases for queued_read_lock()
Add two self test cases for the following case:

	P0:			P1:			P2:

				<in irq handler>
	spin_lock_irq(&slock)	read_lock(&rwlock)
							write_lock_irq(&rwlock)
	read_lock(&rwlock)	spin_lock(&slock)

, which is a deadlock, as the read_lock() on P0 cannot get the lock
because of the fairness.

	P0:			P1:			P2:

	<in irq handler>
	spin_lock(&slock)	read_lock(&rwlock)
							write_lock(&rwlock)
	read_lock(&rwlock)	spin_lock_irq(&slock)

, which is not a deadlock, as the read_lock() on P0 can get the lock
because it could use the unfair fastpass.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-19-boqun.feng@gmail.com
2020-08-26 12:42:07 +02:00
Boqun Feng 108dc42ed3 Revert "locking/lockdep/selftests: Fix mixed read-write ABBA tests"
This reverts commit d82fed7529.

Since we now could handle mixed read-write deadlock detection well, the
self tests could be detected as expected, no need to use this
work-around.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-18-boqun.feng@gmail.com
2020-08-26 12:42:07 +02:00
Boqun Feng 8ef7ca7512 lockdep/selftest: Add more recursive read related test cases
Add those four test cases:

1.	X --(ER)--> Y --(ER)--> Z --(ER)--> X is deadlock.

2.	X --(EN)--> Y --(SR)--> Z --(ER)--> X is deadlock.

3.	X --(EN)--> Y --(SR)--> Z --(SN)--> X is not deadlock.

4.	X --(ER)--> Y --(SR)--> Z --(EN)--> X is not deadlock.

Those self testcases are valuable for the development of supporting
recursive read related deadlock detection.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-17-boqun.feng@gmail.com
2020-08-26 12:42:07 +02:00
Boqun Feng 31e0d74770 lockdep/selftest: Unleash irq_read_recursion2 and add more
Now since we can handle recursive read related irq inversion deadlocks
correctly, uncomment the irq_read_recursion2 and add more testcases.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-16-boqun.feng@gmail.com
2020-08-26 12:42:06 +02:00
Boqun Feng d4f200e579 lockdep/selftest: Add a R-L/L-W test case specific to chain cache behavior
As our chain cache doesn't differ read/write locks, so even we can
detect a read-lock/lock-write deadlock in check_noncircular(), we can
still be fooled if a read-lock/lock-read case(which is not a deadlock)
comes first.

So introduce this test case to test specific to the chain cache behavior
on detecting recursive read lock related deadlocks.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-14-boqun.feng@gmail.com
2020-08-26 12:42:06 +02:00
Boqun Feng e918188611 locking: More accurate annotations for read_lock()
On the archs using QUEUED_RWLOCKS, read_lock() is not always a recursive
read lock, actually it's only recursive if in_interrupt() is true. So
change the annotation accordingly to catch more deadlocks.

Note we used to treat read_lock() as pure recursive read locks in
lib/locking-seftest.c, and this is useful, especially for the lockdep
development selftest, so we keep this via a variable to force switching
lock annotation for read_lock().

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-2-boqun.feng@gmail.com
2020-08-26 12:42:02 +02:00
Marco Elver bec4a24748 kcsan: Test support for compound instrumentation
Changes kcsan-test module to support checking reports that include
compound instrumentation. Since we should not fail the test if this
support is unavailable, we have to add a config variable that the test
can use to decide what to check for.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-08-24 15:09:58 -07:00
Gustavo A. R. Silva 6a9dc5fd61 lib: Revert use of fallthrough pseudo-keyword in lib/
The following build error for powerpc64 was reported by Nathan Chancellor:

  "$ scripts/config --file arch/powerpc/configs/powernv_defconfig -e KERNEL_XZ

   $ make -skj"$(nproc)" ARCH=powerpc CROSS_COMPILE=powerpc64le-linux- distclean powernv_defconfig zImage
   ...
   In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:234,
                    from arch/powerpc/boot/decompress.c:38:
   arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c: In function 'dec_main':
   arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c:586:4: error: 'fallthrough' undeclared (first use in this function)
     586 |    fallthrough;
         |    ^~~~~~~~~~~

   This will end up affecting distribution configurations such as Debian
   and OpenSUSE according to my testing. I am not sure what the solution
   is, the PowerPC wrapper does not set -D__KERNEL__ so I am not sure
   that compiler_attributes.h can be safely included."

In order to avoid these sort of problems, it seems that the best
solution is to use /* fall through */ comments instead of the
fallthrough pseudo-keyword macro in lib/, for now.

Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Fixes: df561f6688 ("treewide: Use fallthrough pseudo-keyword")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-and-tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-24 14:17:44 -07:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Arvind Sankar 33d0f96ffd lib/string.c: Use freestanding environment
gcc can transform the loop in a naive implementation of memset/memcpy
etc into a call to the function itself.  This optimization is enabled by
-ftree-loop-distribute-patterns.

This has been the case for a while, but gcc-10.x enables this option at
-O2 rather than -O3 as in previous versions.

Add -ffreestanding, which implicitly disables this optimization with
gcc.  It is unclear whether clang performs such optimizations, but
hopefully it will also not do so in a freestanding environment.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56888
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-19 11:23:45 -07:00
Krzysztof Kozlowski 8f28ca6bd8 iomap: constify ioreadX() iomem argument (as in generic implementation)
Patch series "iomap: Constify ioreadX() iomem argument", v3.

The ioread8/16/32() and others have inconsistent interface among the
architectures: some taking address as const, some not.

It seems there is nothing really stopping all of them to take pointer to
const.

This patch (of 4):

The ioreadX() and ioreadX_rep() helpers have inconsistent interface.  On
some architectures void *__iomem address argument is a pointer to const,
on some not.

Implementations of ioreadX() do not modify the memory under the address so
they can be converted to a "const" version for const-safety and
consistency among architectures.

[krzk@kernel.org: sh: clk: fix assignment from incompatible pointer type for ioreadX()]
  Link: http://lkml.kernel.org/r/20200723082017.24053-1-krzk@kernel.org
[akpm@linux-foundation.org: fix drivers/mailbox/bcm-pdc-mailbox.c]
  Link: http://lkml.kernel.org/r/202007132209.Rxmv4QyS%25lkp@intel.com

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Jon Mason <jdmason@kudzu.us>
Cc: Allen Hubbe <allenbh@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Link: http://lkml.kernel.org/r/20200709072837.5869-1-krzk@kernel.org
Link: http://lkml.kernel.org/r/20200709072837.5869-2-krzk@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14 19:56:57 -07:00
Nick Terrell b1a3e75e46 lz4: fix kernel decompression speed
This patch replaces all memcpy() calls with LZ4_memcpy() which calls
__builtin_memcpy() so the compiler can inline it.

LZ4 relies heavily on memcpy() with a constant size being inlined.  In x86
and i386 pre-boot environments memcpy() cannot be inlined because memcpy()
doesn't get defined as __builtin_memcpy().

An equivalent patch has been applied upstream so that the next import
won't lose this change [1].

I've measured the kernel decompression speed using QEMU before and after
this patch for the x86_64 and i386 architectures.  The speed-up is about
10x as shown below.

Code	Arch	Kernel Size	Time	Speed
v5.8	x86_64	11504832 B	148 ms	 79 MB/s
patch	x86_64	11503872 B	 13 ms	885 MB/s
v5.8	i386	 9621216 B	 91 ms	106 MB/s
patch	i386	 9620224 B	 10 ms	962 MB/s

I also measured the time to decompress the initramfs on x86_64, i386, and
arm.  All three show the same decompression speed before and after, as
expected.

[1] https://github.com/lz4/lz4/pull/890

Signed-off-by: Nick Terrell <terrelln@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Yann Collet <yann.collet.73@gmail.com>
Cc: Gao Xiang <gaoxiang25@huawei.com>
Cc: Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Link: http://lkml.kernel.org/r/20200803194022.2966806-1-nickrterrell@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14 19:56:56 -07:00
Linus Torvalds b923f1247b A set oftimekeeping/VDSO updates:
- Preparatory work to allow S390 to switch over to the generic VDSO
    implementation.
 
    S390 requires that the VDSO data pointer is handed in to the counter
    read function when time namespace support is enabled. Adding the pointer
    is a NOOP for all other architectures because the compiler is supposed
    to optimize that out when it is unused in the architecture specific
    inline. The change also solved a similar problem for MIPS which
    fortunately has time namespaces not yet enabled.
 
    S390 needs to update clock related VDSO data independent of the
    timekeeping updates. This was solved so far with yet another sequence
    counter in the S390 implementation. A better solution is to utilize the
    already existing VDSO sequence count for this. The core code now exposes
    helper functions which allow to serialize against the timekeeper code
    and against concurrent readers.
 
    S390 needs extra data for their clock readout function. The initial
    common VDSO data structure did not provide a way to add that. It now has
    an embedded architecture specific struct embedded which defaults to an
    empty struct.
 
    Doing this now avoids tree dependencies and conflicts post rc1 and
    allows all other architectures which work on generic VDSO support to
    work from a common upstream base.
 
  - A trivial comment fix.
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Merge tag 'timers-urgent-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timekeeping updates from Thomas Gleixner:
 "A set of timekeeping/VDSO updates:

   - Preparatory work to allow S390 to switch over to the generic VDSO
     implementation.

     S390 requires that the VDSO data pointer is handed in to the
     counter read function when time namespace support is enabled.
     Adding the pointer is a NOOP for all other architectures because
     the compiler is supposed to optimize that out when it is unused in
     the architecture specific inline. The change also solved a similar
     problem for MIPS which fortunately has time namespaces not yet
     enabled.

     S390 needs to update clock related VDSO data independent of the
     timekeeping updates. This was solved so far with yet another
     sequence counter in the S390 implementation. A better solution is
     to utilize the already existing VDSO sequence count for this. The
     core code now exposes helper functions which allow to serialize
     against the timekeeper code and against concurrent readers.

     S390 needs extra data for their clock readout function. The initial
     common VDSO data structure did not provide a way to add that. It
     now has an embedded architecture specific struct embedded which
     defaults to an empty struct.

     Doing this now avoids tree dependencies and conflicts post rc1 and
     allows all other architectures which work on generic VDSO support
     to work from a common upstream base.

   - A trivial comment fix"

* tag 'timers-urgent-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Delete repeated words in comments
  lib/vdso: Allow to add architecture-specific vdso data
  timekeeping/vsyscall: Provide vdso_update_begin/end()
  vdso/treewide: Add vdso_data pointer argument to __arch_get_hw_counter()
2020-08-14 14:26:08 -07:00
Linus Torvalds a1d21081a6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:
 "Some merge window fallout, some longer term fixes:

   1) Handle headroom properly in lapbether and x25_asy drivers, from
      Xie He.

   2) Fetch MAC address from correct r8152 device node, from Thierry
      Reding.

   3) In the sw kTLS path we should allow MSG_CMSG_COMPAT in sendmsg,
      from Rouven Czerwinski.

   4) Correct fdputs in socket layer, from Miaohe Lin.

   5) Revert troublesome sockptr_t optimization, from Christoph Hellwig.

   6) Fix TCP TFO key reading on big endian, from Jason Baron.

   7) Missing CAP_NET_RAW check in nfc, from Qingyu Li.

   8) Fix inet fastreuse optimization with tproxy sockets, from Tim
      Froidcoeur.

   9) Fix 64-bit divide in new SFC driver, from Edward Cree.

  10) Add a tracepoint for prandom_u32 so that we can more easily
      perform usage analysis. From Eric Dumazet.

  11) Fix rwlock imbalance in AF_PACKET, from John Ogness"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (49 commits)
  net: openvswitch: introduce common code for flushing flows
  af_packet: TPACKET_V3: fix fill status rwlock imbalance
  random32: add a tracepoint for prandom_u32()
  Revert "ipv4: tunnel: fix compilation on ARCH=um"
  net: accept an empty mask in /sys/class/net/*/queues/rx-*/rps_cpus
  net: ethernet: stmmac: Disable hardware multicast filter
  net: stmmac: dwmac1000: provide multicast filter fallback
  ipv4: tunnel: fix compilation on ARCH=um
  vsock: fix potential null pointer dereference in vsock_poll()
  sfc: fix ef100 design-param checking
  net: initialize fastreuse on inet_inherit_port
  net: refactor bind_bucket fastreuse into helper
  net: phy: marvell10g: fix null pointer dereference
  net: Fix potential memory leak in proto_register()
  net: qcom/emac: add missed clk_disable_unprepare in error path of emac_clks_phase1_init
  ionic_lif: Use devm_kcalloc() in ionic_qcq_alloc()
  net/nfc/rawsock.c: add CAP_NET_RAW check.
  hinic: fix strncpy output truncated compile warnings
  drivers/net/wan/x25_asy: Added needed_headroom and a skb->len check
  net/tls: Fix kmap usage
  ...
2020-08-13 20:03:11 -07:00
Eric Dumazet 94c7eb54c4 random32: add a tracepoint for prandom_u32()
There has been some heat around prandom_u32() lately, and some people
were wondering if there was a simple way to determine how often
it was used, before considering making it maybe 10 times more expensive.

This tracepoint exports the generated pseudo random value.

Tested:

perf list | grep prandom_u32
  random:prandom_u32                                 [Tracepoint event]

perf record -a [-g] [-C1] -e random:prandom_u32 sleep 1
[ perf record: Woken up 0 times to write data ]
[ perf record: Captured and wrote 259.748 MB perf.data (924087 samples) ]

perf report --nochildren
    ...
    97.67%  ksoftirqd/1     [kernel.vmlinux]  [k] prandom_u32
            |
            ---prandom_u32
               prandom_u32
               |
               |--48.86%--tcp_v4_syn_recv_sock
               |          tcp_check_req
               |          tcp_v4_rcv
               |          ...
                --48.81%--tcp_conn_request
                          tcp_v4_conn_request
                          tcp_rcv_state_process
                          ...
perf script

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-13 15:11:14 -07:00
Tiezhu Yang 9d5b134f9f lib/Kconfig.debug: fix typo in the help text of CONFIG_PANIC_TIMEOUT
There exists duplicated "the" in the help text of CONFIG_PANIC_TIMEOUT,
Remove it.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Xuefeng Li <lixuefeng@loongson.cn>
Link: http://lkml.kernel.org/r/1591103358-32087-2-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:02 -07:00
Tiezhu Yang 0776d1231b test_kmod: avoid potential double free in trigger_config_run_type()
Reset the member "test_fs" of the test configuration after a call of the
function "kfree_const" to a null pointer so that a double memory release
will not be performed.

Fixes: d9c6a72d6f ("kmod: add test driver to stress test the module loader")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David Howells <dhowells@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: James Morris <jmorris@namei.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Sergei Trofimovich <slyfox@gentoo.org>
Cc: Sergey Kvachonok <ravenexp@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Vroon <chainsaw@gentoo.org>
Cc: Christoph Hellwig <hch@infradead.org>
Link: http://lkml.kernel.org/r/20200610154923.27510-4-mcgrof@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:01 -07:00
Rikard Falkeborn 6d511020e1 lib/test_bits.c: add tests of GENMASK
Add tests of GENMASK and GENMASK_ULL.

A few test cases that should fail compilation are provided under #ifdef
TEST_GENMASK_FAILURES

[rd.dunlap@gmail.com: add MODULE_LICENSE()]
  Link: http://lkml.kernel.org/r/dfc74524-0789-2827-4eff-476ddab65699@gmail.com
[weiyongjun1@huawei.com: make some functions static]
  Link: http://lkml.kernel.org/r/20200702150336.4756-1-weiyongjun1@huawei.com

Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Randy Dunlap <rd.dunlap@gmail.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Cc: Syed Nayyar Waris <syednwaris@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Link: http://lkml.kernel.org/r/20200621054210.14804-2-rikard.falkeborn@gmail.com
Link: http://lkml.kernel.org/r/20200608221823.35799-2-rikard.falkeborn@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:00 -07:00
Kars Mulder ef0f268533 kstrto*: do not describe simple_strto*() as obsolete/replaced
The documentation of the kstrto*() functions describes kstrto*() as
"replacements" of the "obsolete" simple_strto*() functions.  Both of these
terms are inaccurate: they're not replacements because they have different
behaviour, and the simple_strto*() are not obsolete because there are
cases where they have benefits over kstrto*().

Remove usage of the terms "replacement" and "obsolete" in reference to
simple_strto*(), and instead use the term "preferred over".

Fixes: 4c925d6031 ("kstrto*: add documentation")
Fixes: 885e68e8b7 ("kernel.h: update comment about simple_strto<foo>() functions")
Signed-off-by: Kars Mulder <kerneldev@karsmulder.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Eldad Zack <eldad@fogrefinery.com>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Mans Rullgard <mans@mansr.com>
Cc: Petr Mladek <pmladek@suse.com>
Link: http://lkml.kernel.org/r/29b9-5f234c80-13-4e3aa200@244003027
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:00 -07:00
Kars Mulder b642e44e8a kstrto*: correct documentation references to simple_strto*()
The documentation of the kstrto*() functions reference the simple_strtoull
function by "used as a replacement for [the obsolete] simple_strtoull".
All these functions describes themselves as replacements for the function
simple_strtoull, even though a function like kstrtol() would be more aptly
described as a replacement of simple_strtol().

Fix these references by making the documentation of kstrto*() reference
the closest simple_strto*() equivalent available.  The functions
kstrto[u]int() do not have direct simple_strto[u]int() equivalences, so
these are made to refer to simple_strto[u]l() instead.

Furthermore, add parentheses after function names, as is standard in
kernel documentation.

Fixes: 4c925d6031 ("kstrto*: add documentation")
Signed-off-by: Kars Mulder <kerneldev@karsmulder.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Eldad Zack <eldad@fogrefinery.com>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Mans Rullgard <mans@mansr.com>
Cc: Petr Mladek <pmladek@suse.com>
Link: http://lkml.kernel.org/r/1ee1-5f234c00-f3-165a6440@234394593
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:00 -07:00