Commit Graph

6397 Commits

Author SHA1 Message Date
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
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
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
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
Alexander A. Klimov
d89775fc92 lib/: replace HTTP links with HTTPS ones
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Coly Li <colyli@suse.de>	[crc64.c]
Link: http://lkml.kernel.org/r/20200726112154.16510-1-grandmaster@al2klimov.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:00 -07:00
Tiezhu Yang
3adf3bae0d lib/test_lockup.c: fix return value of test_lockup_init()
Since filp_open() returns an error pointer, we should use IS_ERR() to
check the return value and then return PTR_ERR() if failed to get the
actual return value instead of always -EINVAL.

E.g. without this patch:

[root@localhost loongson]# ls no_such_file
ls: cannot access no_such_file: No such file or directory
[root@localhost loongson]# modprobe test_lockup file_path=no_such_file lock_sb_umount time_secs=60 state=S
modprobe: ERROR: could not insert 'test_lockup': Invalid argument
[root@localhost loongson]# dmesg | tail -1
[  126.100596] test_lockup: cannot find file_path

With this patch:

[root@localhost loongson]# ls no_such_file
ls: cannot access no_such_file: No such file or directory
[root@localhost loongson]# modprobe test_lockup file_path=no_such_file lock_sb_umount time_secs=60 state=S
modprobe: ERROR: could not insert 'test_lockup': Unknown symbol in module, or unknown parameter (see dmesg)
[root@localhost loongson]# dmesg | tail -1
[   95.134362] test_lockup: failed to open no_such_file: -2

Fixes: aecd42df6d ("lib/test_lockup.c: add parameters for locking generic vfs locks")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/1595555407-29875-2-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:00 -07:00
Tiezhu Yang
63646bc9f9 lib/Kconfig.debug: make TEST_LOCKUP depend on module
Since test_lockup is a test module to generate lockups, it is better to
limit TEST_LOCKUP to module (=m) or disabled (=n) because we can not use
the module parameters when CONFIG_TEST_LOCKUP=y.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/1595555407-29875-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:58:00 -07:00
Wei Yongjun
f363317704 lib/test_lockup.c: make symbol 'test_works' static
Fix sparse build warning:

lib/test_lockup.c:403:1: warning:
 symbol '__pcpu_scope_test_works' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200707112252.9047-1-weiyongjun1@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:59 -07:00
Geert Uytterhoeven
403f177304 lib/test_bitops: do the full test during module init
Currently, the bitops test consists of two parts: one part is executed
during module load, the second part during module unload.  This is
cumbersome for the user, as he has to perform two steps to execute all
tests, and is different from most (all?) other tests.

Merge the two parts, so both are executed during module load.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Jesse Brandeburg <jesse.brandeburg@intel.com>
Link: http://lkml.kernel.org/r/20200706112900.7097-1-geert@linux-m68k.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:59 -07:00
Stefano Brivio
bcb32a1d82 lib/test_bitmap.c: add test for bitmap_cut()
Inspired by an original patch from Yury Norov: introduce a test for
bitmap_cut() that also makes sure functionality is as described for
partially overlapping src and dst.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Yury Norov <yury.norov@gmail.com>
Link: http://lkml.kernel.org/r/5fc45e6bbd4fa837cd9577f8a0c1d639df90a4ce.1592155364.git.sbrivio@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:59 -07:00
Stefano Brivio
5959f829a9 lib/bitmap.c: fix bitmap_cut() for partial overlapping case
Patch series "lib: Fix bitmap_cut() for overlaps, add test"

This patch (of 2):

Yury Norov reports that bitmap_cut() will not produce the right outcome if
src and dst partially overlap, with src pointing at some location after
dst, because the memmove() affects src before we store the bits that we
need to keep, that is, the bits preceding the cut -- as long as we the
beginning of the cut is not aligned to a long.

Fix this by storing those bits before the memmove().

Note that this is just a theoretical concern so far, as the only user of
this function, pipapo_drop() from the nftables set back-end implemented in
net/netfilter/nft_set_pipapo.c, always supplies entirely overlapping src
and dst.

Fixes: 2092767168 ("bitmap: Introduce bitmap_cut(): cut bits and shift remaining")
Reported-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Link: http://lkml.kernel.org/r/cover.1592155364.git.sbrivio@redhat.com
Link: http://lkml.kernel.org/r/003e38d4428cd6091ef00b5b03354f1bd7d9091e.1592155364.git.sbrivio@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:59 -07:00
Feng Tang
09c60546f0 ./Makefile: add debug option to enable function aligned on 32 bytes
Recently 0day reported many strange performance changes (regression or
improvement), in which there was no obvious relation between the culprit
commit and the benchmark at the first look, and it causes people to doubt
the test itself is wrong.

Upon further check, many of these cases are caused by the change to the
alignment of kernel text or data, as whole text/data of kernel are linked
together, change in one domain may affect alignments of other domains.

gcc has an option '-falign-functions=n' to force text aligned, and with
that option enabled, some of those performance changes will be gone, like
[1][2][3].

Add this option so that developers and 0day can easily find performance
bump caused by text alignment change, as tracking these strange bump is
quite time consuming.  Though it can't help in other cases like data
alignment changes like [4].

Following is some size data for v5.7 kernel built with a RHEL config used
in 0day:

    text      data      bss	 dec	   filename
  19738771  13292906  5554236  38585913	 vmlinux.noalign
  19758591  13297002  5529660  38585253	 vmlinux.align32

Raw vmlinux size in bytes:

	v5.7		v5.7+align32
	253950832	254018000	+0.02%

Some benchmark data, most of them have no big change:

  * hackbench:		[ -1.8%,  +0.5%]

  * fsmark:		[ -3.2%,  +3.4%]  # ext4/xfs/btrfs

  * kbuild:		[ -2.0%,  +0.9%]

  * will-it-scale:	[ -0.5%,  +1.8%]  # mmap1/pagefault3

  * netperf:
    - TCP_CRR		[+16.6%, +97.4%]
    - TCP_RR		[-18.5%,  -1.8%]
    - TCP_STREAM	[ -1.1%,  +1.9%]

[1] https://lore.kernel.org/lkml/20200114085637.GA29297@shao2-debian/
[2] https://lore.kernel.org/lkml/20200330011254.GA14393@feng-iot/
[3] https://lore.kernel.org/lkml/1d98d1f0-fe84-6df7-f5bd-f4cb2cdb7f45@intel.com/
[4] https://lore.kernel.org/lkml/20200205123216.GO12867@shao2-debian/

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@intel.com>
Link: http://lkml.kernel.org/r/1595475001-90945-1-git-send-email-feng.tang@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:59 -07:00
Linus Torvalds
fc80c51fd4 Kbuild updates for v5.9
- run the checker (e.g. sparse) after the compiler
 
  - remove unneeded cc-option tests for old compiler flags
 
  - fix tar-pkg to install dtbs
 
  - introduce ccflags-remove-y and asflags-remove-y syntax
 
  - allow to trace functions in sub-directories of lib/
 
  - introduce hostprogs-always-y and userprogs-always-y syntax
 
  - various Makefile cleanups
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Merge tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - run the checker (e.g. sparse) after the compiler

 - remove unneeded cc-option tests for old compiler flags

 - fix tar-pkg to install dtbs

 - introduce ccflags-remove-y and asflags-remove-y syntax

 - allow to trace functions in sub-directories of lib/

 - introduce hostprogs-always-y and userprogs-always-y syntax

 - various Makefile cleanups

* tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base
  kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled
  kbuild: introduce hostprogs-always-y and userprogs-always-y
  kbuild: sort hostprogs before passing it to ifneq
  kbuild: move host .so build rules to scripts/gcc-plugins/Makefile
  kbuild: Replace HTTP links with HTTPS ones
  kbuild: trace functions in subdirectories of lib/
  kbuild: introduce ccflags-remove-y and asflags-remove-y
  kbuild: do not export LDFLAGS_vmlinux
  kbuild: always create directories of targets
  powerpc/boot: add DTB to 'targets'
  kbuild: buildtar: add dtbs support
  kbuild: remove cc-option test of -ffreestanding
  kbuild: remove cc-option test of -fno-stack-protector
  Revert "kbuild: Create directory for target DTB"
  kbuild: run the checker after the compiler
2020-08-09 14:10:26 -07:00
Masahiro Yamada
b16838c608 kbuild: trace functions in subdirectories of lib/
ccflags-remove-$(CONFIG_FUNCTION_TRACER) += $(CC_FLAGS_FTRACE)

exists here in sub-directories of lib/ to keep the behavior of
commit 2464a609de ("ftrace: do not trace library functions").

Since that commit, not only the objects in lib/ but also the ones in
the sub-directories are excluded from ftrace (although the commit
description did not explicitly mention this).

However, most of library functions in sub-directories are not so hot.
Re-add them to ftrace.

Going forward, only the objects right under lib/ will be excluded.

Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-08-10 01:32:59 +09:00
Masahiro Yamada
15d5761ad3 kbuild: introduce ccflags-remove-y and asflags-remove-y
CFLAGS_REMOVE_<file>.o filters out flags when compiling a particular
object, but there is no convenient way to do that for every object in
a directory.

Add ccflags-remove-y and asflags-remove-y to make it easily.

Use ccflags-remove-y to clean up some Makefiles.

The add/remove order works as follows:

 [1] KBUILD_CFLAGS specifies compiler flags used globally

 [2] ccflags-y adds compiler flags for all objects in the
     current Makefile

 [3] ccflags-remove-y removes compiler flags for all objects in the
     current Makefile (New feature)

 [4] CFLAGS_<file> adds compiler flags per file.

 [5] CFLAGS_REMOVE_<file> removes compiler flags per file.

Having [3] before [4] allows us to remove flags from most (but not all)
objects in the current Makefile.

For example, kernel/trace/Makefile removes $(CC_FLAGS_FTRACE)
from all objects in the directory, then adds it back to
trace_selftest_dynamic.o and CFLAGS_trace_kprobe_selftest.o

The same applies to lib/livepatch/Makefile.

Please note ccflags-remove-y has no effect to the sub-directories.
In contrast, the previous notation got rid of compiler flags also from
all the sub-directories.

The following are not affected because they have no sub-directories:

  arch/arm/boot/compressed/
  arch/powerpc/xmon/
  arch/sh/
  kernel/trace/

However, lib/ has several sub-directories.

To keep the behavior, I added ccflags-remove-y to all Makefiles
in subdirectories of lib/, except the following:

  lib/vdso/Makefile        - Kbuild does not descend into this Makefile
  lib/raid/test/Makefile   - This is not used for the kernel build

I think commit 2464a609de ("ftrace: do not trace library functions")
excluded too much. In the next commit, I will remove ccflags-remove-y
from the sub-directories of lib/.

Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Brendan Higgins <brendanhiggins@google.com> (KUnit)
Tested-by: Anders Roxell <anders.roxell@linaro.org>
2020-08-10 01:32:59 +09:00
Linus Torvalds
b79675e15a Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "No common topic whatsoever in those, sorry"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: define inode flags using bit numbers
  iov_iter: Move unnecessary inclusion of crypto/hash.h
  dlmfs: clean up dlmfs_file_{read,write}() a bit
2020-08-07 21:14:30 -07:00
Linus Torvalds
32663c78c1 Tracing updates for 5.9
- The biggest news in that the tracing ring buffer can now time events that
    interrupted other ring buffer events. Before this change, if an interrupt
    came in while recording another event, and that interrupt also had an
    event, those events would all have the same time stamp as the event it
    interrupted. Now, with the new design, those events will have a unique time
    stamp and rightfully display the time for those events that were recorded
    while interrupting another event.
 
  - Bootconfig how has an "override" operator that lets the users have a
    default config, but then add options to override the default.
 
  - A fix was made to properly filter function graph tracing to the ftrace
    PIDs. This came in at the end of the -rc cycle, and needs to be backported.
 
  - Several clean ups, performance updates, and minor fixes as well.
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Merge tag 'trace-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - The biggest news in that the tracing ring buffer can now time events
   that interrupted other ring buffer events.

   Before this change, if an interrupt came in while recording another
   event, and that interrupt also had an event, those events would all
   have the same time stamp as the event it interrupted.

   Now, with the new design, those events will have a unique time stamp
   and rightfully display the time for those events that were recorded
   while interrupting another event.

 - Bootconfig how has an "override" operator that lets the users have a
   default config, but then add options to override the default.

 - A fix was made to properly filter function graph tracing to the
   ftrace PIDs. This came in at the end of the -rc cycle, and needs to
   be backported.

 - Several clean ups, performance updates, and minor fixes as well.

* tag 'trace-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (39 commits)
  tracing: Add trace_array_init_printk() to initialize instance trace_printk() buffers
  kprobes: Fix compiler warning for !CONFIG_KPROBES_ON_FTRACE
  tracing: Use trace_sched_process_free() instead of exit() for pid tracing
  bootconfig: Fix to find the initargs correctly
  Documentation: bootconfig: Add bootconfig override operator
  tools/bootconfig: Add testcases for value override operator
  lib/bootconfig: Add override operator support
  kprobes: Remove show_registers() function prototype
  tracing/uprobe: Remove dead code in trace_uprobe_register()
  kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler
  ftrace: Fix ftrace_trace_task return value
  tracepoint: Use __used attribute definitions from compiler_attributes.h
  tracepoint: Mark __tracepoint_string's __used
  trace : Have tracing buffer info use kvzalloc instead of kzalloc
  tracing: Remove outdated comment in stack handling
  ftrace: Do not let direct or IPMODIFY ftrace_ops be added to module and set trampolines
  ftrace: Setup correct FTRACE_FL_REGS flags for module
  tracing/hwlat: Honor the tracing_cpumask
  tracing/hwlat: Drop the duplicate assignment in start_kthread()
  tracing: Save one trace_event->type by using __TRACE_LAST_TYPE
  ...
2020-08-07 18:29:15 -07:00
Andrey Konovalov
51dcc81c28 kasan: adjust kasan_stack_oob for tag-based mode
Use OOB_TAG_OFF as access offset to land the access into the next granule.

Suggested-by: Walter Wu <walter-zh.wu@mediatek.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Elena Petrova <lenaptr@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Link: http://lkml.kernel.org/r/403b259f1de49a7a3694531c851ac28326a586a8.1596199677.git.andreyknvl@google.com
Link: http://lkml.kernel.org/r/3063ab1411e92bce36061a96e25b651212e70ba6.1596544734.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:28 -07:00
Walter Wu
f33a01492a lib/test_kasan.c: fix KASAN unit tests for tag-based KASAN
We use tag-based KASAN, then KASAN unit tests don't detect out-of-bounds
memory access. They need to be fixed.

With tag-based KASAN, the state of each 16 aligned bytes of memory is
encoded in one shadow byte and the shadow value is tag of pointer, so
we need to read next shadow byte, the shadow value is not equal to tag
value of pointer, so that tag-based KASAN will detect out-of-bounds
memory access.

[walter-zh.wu@mediatek.com: use KASAN_SHADOW_SCALE_SIZE instead of 13]
  Link: http://lkml.kernel.org/r/20200708132524.11688-1-walter-zh.wu@mediatek.com

Suggested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Link: http://lkml.kernel.org/r/20200706115039.16750-1-walter-zh.wu@mediatek.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:28 -07:00
Walter Wu
387d6e4668 kasan: add tests for call_rcu stack recording
Test call_rcu() call stack recording and verify whether it correctly is
printed in KASAN report.

Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Link: http://lkml.kernel.org/r/20200601051045.1294-1-walter-zh.wu@mediatek.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:28 -07:00
Marco Elver
ac4766be5e kasan: update required compiler versions in documentation
Updates the recently changed compiler requirements for KASAN.  In
particular, we require GCC >= 8.3.0, and add a note that Clang 11 supports
OOB detection of globals.

Fixes: 7b861a53e4 ("kasan: Bump required compiler version")
Fixes: acf7b0bf7d ("kasan: Fix required compiler version")
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Walter Wu <walter-zh.wu@mediatek.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Axtens <dja@axtens.net>
Link: http://lkml.kernel.org/r/20200629104157.3242503-2-elver@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:28 -07:00
Marco Elver
7a3767f83f kasan: improve and simplify Kconfig.kasan
Turn 'KASAN' into a menuconfig, to avoid cluttering its parent menu with
the suboptions if enabled.  Use 'if KASAN ...  endif' instead of having to
'depend on KASAN' for each entry.

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Walter Wu <walter-zh.wu@mediatek.com>
Link: http://lkml.kernel.org/r/20200629104157.3242503-1-elver@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:28 -07:00
Feng Tang
0a4954a850 percpu_counter: add percpu_counter_sync()
percpu_counter's accuracy is related to its batch size.  For a
percpu_counter with a big batch, its deviation could be big, so when the
counter's batch is runtime changed to a smaller value for better accuracy,
there could also be requirment to reduce the big deviation.

So add a percpu-counter sync function to be run on each CPU.

Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Tim Chen <tim.c.chen@intel.com>
Link: http://lkml.kernel.org/r/1594389708-60781-4-git-send-email-feng.tang@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:26 -07:00