Patch series "lib: rework bitmap_parselist and tests", v5.
bitmap_parselist has been evolved from a pretty simple idea for long and
now lacks for refactoring. It is not structured, has nested loops and a
set of opaque-named variables.
Things are more complicated because bitmap_parselist() is a part of user
interface, and its behavior should not change.
In this patchset
- bitmap_parselist_user() made a wrapper on bitmap_parselist();
- bitmap_parselist() reworked (patch 2);
- time measurement in test_bitmap_parselist switched to ktime_get
(patch 3);
- new tests introduced (patch 4), and
- bitmap_parselist_user() testing enabled with the same testset as
bitmap_parselist() (patch 5).
This patch (of 5):
Currently we parse user data byte after byte which leads to
overcomplification of parsing algorithm. The only user of
bitmap_parselist_user() is not performance-critical, and so we can
duplicate user data to kernel buffer and simply call bitmap_parselist().
This rework lets us unify and simplify bitmap_parselist() and
bitmap_parselist_user(), which is done in the following patch.
Link: http://lkml.kernel.org/r/20190405173211.11373-2-ynorov@marvell.com
Signed-off-by: Yury Norov <ynorov@marvell.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Mike Travis <travis@sgi.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
The bitmap_remap, _bitremap, _onto and _fold functions are only used,
via their node_ wrappers, in mm/mempolicy.c, which is only built for
CONFIG_NUMA. The helper bitmap_ord_to_pos used by these functions is
global, but its only external caller is node_random() in lib/nodemask.c,
which is also guarded by CONFIG_NUMA.
For !CONFIG_NUMA:
add/remove: 0/6 grow/shrink: 0/0 up/down: 0/-621 (-621)
Function old new delta
bitmap_pos_to_ord 20 - -20
bitmap_ord_to_pos 70 - -70
bitmap_bitremap 81 - -81
bitmap_fold 113 - -113
bitmap_onto 123 - -123
bitmap_remap 214 - -214
Total: Before=4776, After=4155, chg -13.00%
Link: http://lkml.kernel.org/r/20190329205353.6010-2-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
AFAICT, there have never been any callers of these functions outside
mm/mempolicy.c (via their nodemask.h wrappers). In particular, no
modular code has ever used them, and given their somewhat exotic
semantics, I highly doubt they will ever find such a use. In any case,
no need to export them currently.
Link: http://lkml.kernel.org/r/20190329205353.6010-1-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
len is guaranteed to lie in [1, PAGE_SIZE]. If scnprintf is called with a
buffer size of 1, it is guaranteed to return 0. So in the extremely
unlikely case of having just one byte remaining in the page, let's just
call scnprintf anyway. The only difference is that this will write a '\0'
to that final byte in the page, but that's an improvement: We now
guarantee that after the call, buf is a properly terminated C string of
length exactly the return value.
Link: http://lkml.kernel.org/r/20180818131623.8755-8-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Yury Norov <ynorov@caviumnetworks.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
For various alignments of buf, the current expression computes
4096 ok
4095 ok
8190
8189
...
4097
i.e., if the caller has already written two bytes into the page buffer,
len is 8190 rather than 4094, because PTR_ALIGN aligns up to the next
boundary. So if the printed version of the bitmap is huge, scnprintf()
ends up writing beyond the page boundary.
I don't think any current callers actually write anything before
bitmap_print_to_pagebuf, but the API seems to be designed to allow it.
[akpm@linux-foundation.org: use offset_in_page(), per Andy]
[akpm@linux-foundation.org: include mm.h for offset_in_page()]
Link: http://lkml.kernel.org/r/20180818131623.8755-7-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Yury Norov <ynorov@caviumnetworks.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
It's not clear what's so horrible about emitting a function call to handle
a run-time sized bitmap. Moreover, gcc also emits a function call for a
compile-time-constant-but-huge nbits, so the comment isn't even accurate.
Link: http://lkml.kernel.org/r/20180818131623.8755-6-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Yury Norov <ynorov@caviumnetworks.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
This promise is violated in a number of places, e.g. already in the
second function below this paragraph. Since I don't think anybody relies
on this being true, and since actually honouring it would hurt performance
and code size in various places, just remove the paragraph.
Link: http://lkml.kernel.org/r/20180818131623.8755-2-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Yury Norov <ynorov@caviumnetworks.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
nbits == 0 is safe to be supplied to the function body, so remove
unnecessary checks in bitmap_to_arr32() and bitmap_from_arr32().
Link: http://lkml.kernel.org/r/20180531131914.44352-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
Use BITS_TO_LONGS() macro to avoid calculation of reminder (bits %
BITS_PER_LONG) On ARM64 it saves 5 instruction for function - 16 before
and 11 after.
Link: http://lkml.kernel.org/r/20180411145914.6011-1-ynorov@caviumnetworks.com
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
syzbot is catching stalls at __bitmap_parselist()
(https://syzkaller.appspot.com/bug?id=ad7e0351fbc90535558514a71cd3edc11681997a).
The trigger is
unsigned long v = 0;
bitmap_parselist("7:,", &v, BITS_PER_LONG);
which results in hitting infinite loop at
while (a <= b) {
off = min(b - a + 1, used_size);
bitmap_set(maskp, a, off);
a += group_size;
}
due to used_size == group_size == 0.
Link: http://lkml.kernel.org/r/20180404162647.15763-1-ynorov@caviumnetworks.com
Fixes: 0a5ce0831d04382a ("lib/bitmap.c: make bitmap_parselist() thread-safe and much faster")
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+6887cbb011c8054e8a3d@syzkaller.appspotmail.com>
Cc: Noam Camus <noamca@mellanox.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
Commit 2a98dc028f91 ("include/linux/bitmap.h: turn bitmap_set and
bitmap_clear into memset when possible") introduced an optimization to
bitmap_{set,clear}() which uses memset() when the start and length are
constants aligned to a byte.
This is wrong on big-endian systems; our bitmaps are arrays of unsigned
long, so bit n is not at byte n / 8 in memory. This was caught by the
Btrfs selftests, but the bitmap selftests also fail when run on a
big-endian machine.
We can still use memset if the start and length are aligned to an
unsigned long, so do that on big-endian. The same problem applies to
the memcmp in bitmap_equal(), so fix it there, too.
Fixes: 2a98dc028f91 ("include/linux/bitmap.h: turn bitmap_set and bitmap_clear into memset when possible")
Fixes: 2c6deb01525a ("bitmap: use memcmp optimisation in more situations")
Cc: stable@kernel.org
Reported-by: "Erhard F." <erhard_f@mailbox.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
Behaviour of bitmap_fill() differs from bitmap_zero() in a way how bits
behind bitmap are handed. bitmap_zero() clears entire bitmap by unsigned
long boundary, while bitmap_fill() mimics bitmap_set().
Here we change bitmap_fill() behaviour to be consistent with bitmap_zero()
and add a note to documentation.
The change might reveal some bugs in the code where unused bits are
handled differently and in such cases bitmap_set() has to be used.
Link: http://lkml.kernel.org/r/20180109172430.87452-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
with bitmap_{from,to}_arr32 over the kernel. Additionally to it:
* __check_eq_bitmap() now takes single nbits argument.
* __check_eq_u32_array is not used in new test but may be used in
future. So I don't remove it here, but annotate as __used.
Tested on arm64 and 32-bit BE mips.
[arnd@arndb.de: perf: arm_dsu_pmu: convert to bitmap_from_arr32]
Link: http://lkml.kernel.org/r/20180201172508.5739-2-ynorov@caviumnetworks.com
[ynorov@caviumnetworks.com: fix net/core/ethtool.c]
Link: http://lkml.kernel.org/r/20180205071747.4ekxtsbgxkj5b2fz@yury-thinkpad
Link: http://lkml.kernel.org/r/20171228150019.27953-2-ynorov@caviumnetworks.com
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: David Decotigny <decot@googlers.com>,
Cc: David S. Miller <davem@davemloft.net>,
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
This patchset replaces bitmap_{to,from}_u32array with more simple and
standard looking copy-like functions.
bitmap_from_u32array() takes 4 arguments (bitmap_to_u32array is similar):
- unsigned long *bitmap, which is destination;
- unsigned int nbits, the length of destination bitmap, in bits;
- const u32 *buf, the source; and
- unsigned int nwords, the length of source buffer in ints.
In description to the function it is detailed like:
* copy min(nbits, 32*nwords) bits from @buf to @bitmap, remaining
* bits between nword and nbits in @bitmap (if any) are cleared.
Having two size arguments looks unneeded and potentially dangerous.
It is unneeded because normally user of copy-like function should take
care of the size of destination and make it big enough to fit source
data.
And it is dangerous because function may hide possible error if user
doesn't provide big enough bitmap, and data becomes silently dropped.
That's why all copy-like functions have 1 argument for size of copying
data, and I don't see any reason to make bitmap_from_u32array()
different.
One exception that comes in mind is strncpy() which also provides size
of destination in arguments, but it's strongly argued by the possibility
of taking broken strings in source. This is not the case of
bitmap_{from,to}_u32array().
There is no many real users of bitmap_{from,to}_u32array(), and they all
very clearly provide size of destination matched with the size of
source, so additional functionality is not used in fact. Like this:
bitmap_from_u32array(to->link_modes.supported,
__ETHTOOL_LINK_MODE_MASK_NBITS,
link_usettings.link_modes.supported,
__ETHTOOL_LINK_MODE_MASK_NU32);
Where:
DIV_ROUND_UP(__ETHTOOL_LINK_MODE_MASK_NBITS, 32)
In this patch, bitmap_copy_safe and bitmap_{from,to}_arr32 are introduced.
'Safe' in bitmap_copy_safe() stands for clearing unused bits in bitmap
beyond last bit till the end of last word. It is useful for hardening
API when bitmap is assumed to be exposed to userspace.
bitmap_{from,to}_arr32 functions are replacements for
bitmap_{from,to}_u32array. They don't take unneeded nwords argument, and
so simpler in implementation and understanding.
This patch suggests optimization for 32-bit systems - aliasing
bitmap_{from,to}_arr32 to bitmap_copy_safe.
Other possible optimization is aliasing 64-bit LE bitmap_{from,to}_arr32 to
more generic function(s). But I didn't end up with the function that would
be helpful by itself, and can be used to alias 64-bit LE
bitmap_{from,to}_arr32, like bitmap_copy_safe() does. So I preferred to
leave things as is.
The following patch switches kernel to new API and introduces test for it.
Discussion is here: https://lkml.org/lkml/2017/11/15/592
[ynorov@caviumnetworks.com: rename bitmap_copy_safe to bitmap_copy_clear_tail]
Link: http://lkml.kernel.org/r/20180201172508.5739-3-ynorov@caviumnetworks.com
Link: http://lkml.kernel.org/r/20171228150019.27953-1-ynorov@caviumnetworks.com
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: David Decotigny <decot@googlers.com>,
Cc: David S. Miller <davem@davemloft.net>,
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
There are some good comments about bitmap operations in lib/bitmap.c
and include/linux/bitmap.h, so format them for document generation and
pull them into core-api/kernel-api.rst.
I converted the "tables" of functions from using tabs to using spaces
so that they are more readable in the source file and in the generated
output.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
This reverts commit ac5a36bb69570bc5bdd68f21c6793abc0b110cb7.
Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
This reverts commit a333a284fff29db8e68acf14f39432be9c63eb1b.
Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
Signed-off-by: alk3pInjection <webmaster@raspii.tech>
Signed-off-by: azrim <mirzaspc@gmail.com>
In general, as of now, in FUSE, direct writes on the same file are
serialized over inode lock i.e we hold inode lock for the full duration
of the write request. I could not found in fuse code a comment which
clearly explains why this exclusive lock is taken for direct writes.
Our guess is some USER space fuse implementations might be relying
on this lock for seralization and also it protects for the issues
arising due to file size assumption or write failures. This patch
relaxes this exclusive lock in some cases of direct writes.
With these changes, we allows non-extending parallel direct writes
on the same file with the help of a flag called FOPEN_PARALLEL_WRITES.
If this flag is set on the file (flag is passed from libfuse to fuse
kernel as part of file open/create), we do not take exclusive lock instead
use shared lock so that all non-extending writes can run in parallel.
Best practise would be to enable parallel direct writes of all kinds
including extending writes as well but we see some issues such as
when one write completes and other fails, how we should truncate(if
needed) the file if underlying file system does not support holes
(For file systems which supports holes, there might be a possibility
of enabling parallel writes for all cases).
FUSE implementations which rely on this inode lock for serialisation
can continue to do so and this is default behaviour i.e no parallel
direct writes.
Signed-off-by: Dharmendra Singh <dsingh@ddn.com>
[cyberknight777: backport and adapt to 4.14 fuse implementation]
Signed-off-by: Cyber Knight <cyberknight755@gmail.com>
Signed-off-by: azrim <mirzaspc@gmail.com>
LZ4 final literal copy could be overlapped when doing
in-place decompression, so it's unsafe to just use memcpy()
on an optimized memcpy approach but memmove() instead.
Upstream LZ4 has updated this years ago [1] (and the impact
is non-sensible [2] plus only a few bytes remain), this commit
just synchronizes LZ4 upstream code to the kernel side as well.
It can be observed as EROFS in-place decompression failure
on specific files when X86_FEATURE_ERMS is unsupported,
memcpy() optimization of commit 59daa706fbec ("x86, mem:
Optimize memcpy by avoiding memory false dependece") will
be enabled then.
Currently most modern x86-CPUs support ERMS, these CPUs just
use "rep movsb" approach so no problem at all. However, it can
still be verified with forcely disabling ERMS feature...
arch/x86/lib/memcpy_64.S:
ALTERNATIVE_2 "jmp memcpy_orig", "", X86_FEATURE_REP_GOOD, \
- "jmp memcpy_erms", X86_FEATURE_ERMS
+ "jmp memcpy_orig", X86_FEATURE_ERMS
We didn't observe any strange on arm64/arm/x86 platform before
since most memcpy() would behave in an increasing address order
("copy upwards" [3]) and it's the correct order of in-place
decompression but it really needs an update to memmove() for sure
considering it's an undefined behavior according to the standard
and some unique optimization already exists in the kernel.
[1] 33cb8518ac
[2] https://github.com/lz4/lz4/pull/717#issuecomment-497818921
[3] https://sourceware.org/bugzilla/show_bug.cgi?id=12518
Link: https://lkml.kernel.org/r/20201122030749.2698994-1-hsiangkao@redhat.com
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Nick Terrell <terrelln@fb.com>
Cc: Yann Collet <yann.collet.73@gmail.com>
Cc: Miao Xie <miaoxie@huawei.com>
Cc: Chao Yu <yuchao0@huawei.com>
Cc: Li Guifu <bluce.liguifu@huawei.com>
Cc: Guo Xuenan <guoxuenan@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 89b158635ad79574bde8e94d45dad33f8cf09549)
Signed-off-by: Panchajanya1999 <panchajanya@azure-dev.live>
Change-Id: Ib192a9a7cf891b201ff2be476e60fc01c8a33652
Signed-off-by: Cyber Knight <cyberknight755@gmail.com>
Signed-off-by: azrim <mirzaspc@gmail.com>
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>
(cherry picked from commit b1a3e75e466d96383508634f3d2e477ac45f2fc1)
Signed-off-by: Panchajanya1999 <panchajanya@azure-dev.live>
Change-Id: I5345e2d16f7e552f437aae2015905ff121ad752d
Signed-off-by: Cyber Knight <cyberknight755@gmail.com>
Signed-off-by: azrim <mirzaspc@gmail.com>
This operation was intentional, but tools such as smatch will warn that it
might not have been.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Yann Collet <cyan@fb.com>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: Gao Xiang <hsiangkao@aol.com>
Link: http://lkml.kernel.org/r/3bf931c6ea0cae3e23f3485801986859851b4f04.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit e8ec04938c446e5f4dc53e0147f0f679995012ee)
Signed-off-by: Panchajanya1999 <panchajanya@azure-dev.live>
Change-Id: I0686513a159bcb74c7f22337fafb1c65782bf9cd
Signed-off-by: Cyber Knight <cyberknight755@gmail.com>
Signed-off-by: azrim <mirzaspc@gmail.com>
* google/android-4.14-stable:
ANDROID: android-verity: Prevent double-freeing metadata
Linux 4.14.282
bpf: Enlarge offset check value to INT_MAX in bpf_skb_{load,store}_bytes
NFSD: Fix possible sleep during nfsd4_release_lockowner()
docs: submitting-patches: Fix crossref to 'The canonical patch format'
tpm: ibmvtpm: Correct the return value in tpm_ibmvtpm_probe()
dm verity: set DM_TARGET_IMMUTABLE feature flag
dm stats: add cond_resched when looping over entries
dm crypt: make printing of the key constant-time
dm integrity: fix error code in dm_integrity_ctr()
zsmalloc: fix races between asynchronous zspage free and page migration
netfilter: conntrack: re-fetch conntrack after insertion
exec: Force single empty string when argv is empty
block-map: add __GFP_ZERO flag for alloc_page in function bio_copy_kern
drm/i915: Fix -Wstringop-overflow warning in call to intel_read_wm_latency()
assoc_array: Fix BUG_ON during garbage collect
drivers: i2c: thunderx: Allow driver to work with ACPI defined TWSI controllers
net: ftgmac100: Disable hardware checksum on AST2600
net: af_key: check encryption module availability consistency
ACPI: sysfs: Fix BERT error region memory mapping
ACPI: sysfs: Make sparse happy about address space in use
secure_seq: use the 64 bits of the siphash for port offset calculation
tcp: change source port randomizarion at connect() time
staging: rtl8723bs: prevent ->Ssid overflow in rtw_wx_set_scan()
x86/pci/xen: Disable PCI/MSI[-X] masking for XEN_HVM guests
Linux 4.14.281
Reinstate some of "swiotlb: rework "fix info leak with DMA_FROM_DEVICE""
swiotlb: fix info leak with DMA_FROM_DEVICE
net: atlantic: verify hw_head_ lies within TX buffer ring
net: stmmac: fix missing pci_disable_device() on error in stmmac_pci_probe()
ethernet: tulip: fix missing pci_disable_device() on error in tulip_init_one()
mac80211: fix rx reordering with non explicit / psmp ack policy
scsi: qla2xxx: Fix missed DMA unmap for aborted commands
perf bench numa: Address compiler error on s390
gpio: mvebu/pwm: Refuse requests with inverted polarity
gpio: gpio-vf610: do not touch other bits when set the target bit
net: bridge: Clear offload_fwd_mark when passing frame up bridge interface.
igb: skip phy status check where unavailable
ARM: 9197/1: spectre-bhb: fix loop8 sequence for Thumb2
ARM: 9196/1: spectre-bhb: enable for Cortex-A15
net: af_key: add check for pfkey_broadcast in function pfkey_process
NFC: nci: fix sleep in atomic context bugs caused by nci_skb_alloc
net/qla3xxx: Fix a test in ql_reset_work()
clk: at91: generated: consider range when calculating best rate
net: vmxnet3: fix possible NULL pointer dereference in vmxnet3_rq_cleanup()
net: vmxnet3: fix possible use-after-free bugs in vmxnet3_rq_alloc_rx_buf()
mmc: core: Default to generic_cmd6_time as timeout in __mmc_switch()
mmc: block: Use generic_cmd6_time when modifying INAND_CMD38_ARG_EXT_CSD
mmc: core: Specify timeouts for BKOPS and CACHE_FLUSH for eMMC
drm/dp/mst: fix a possible memory leak in fetch_monitor_name()
perf: Fix sys_perf_event_open() race against self
ALSA: wavefront: Proper check of get_user() error
ARM: 9191/1: arm/stacktrace, kasan: Silence KASAN warnings in unwind_frame()
drbd: remove usage of list iterator variable after loop
MIPS: lantiq: check the return value of kzalloc()
Input: stmfts - fix reference leak in stmfts_input_open
Input: add bounds checking to input_set_capability()
um: Cleanup syscall_handler_t definition/cast, fix warning
floppy: use a statically allocated error counter
If extract_metadata() fails, it will free metadata in its own error
path, so it is safe to simply return the provided error value without
worrying about resource handling/releasing.
Moreover, if we simply return in extract_metadata()'s error path, we
can assume the thread of execution will only make it down into the
free_metadata: tag area sometime after extract_metadata()'s success,
in which case metadata will need to be freed without question.
Bug: 234030265
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Change-Id: I1bf42ff9ecef3eea26543526c6955d7823d45c43
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Merge 4.14.282 into android-4.14-stable
Changes in 4.14.282
x86/pci/xen: Disable PCI/MSI[-X] masking for XEN_HVM guests
staging: rtl8723bs: prevent ->Ssid overflow in rtw_wx_set_scan()
tcp: change source port randomizarion at connect() time
secure_seq: use the 64 bits of the siphash for port offset calculation
ACPI: sysfs: Make sparse happy about address space in use
ACPI: sysfs: Fix BERT error region memory mapping
net: af_key: check encryption module availability consistency
net: ftgmac100: Disable hardware checksum on AST2600
drivers: i2c: thunderx: Allow driver to work with ACPI defined TWSI controllers
assoc_array: Fix BUG_ON during garbage collect
drm/i915: Fix -Wstringop-overflow warning in call to intel_read_wm_latency()
block-map: add __GFP_ZERO flag for alloc_page in function bio_copy_kern
exec: Force single empty string when argv is empty
netfilter: conntrack: re-fetch conntrack after insertion
zsmalloc: fix races between asynchronous zspage free and page migration
dm integrity: fix error code in dm_integrity_ctr()
dm crypt: make printing of the key constant-time
dm stats: add cond_resched when looping over entries
dm verity: set DM_TARGET_IMMUTABLE feature flag
tpm: ibmvtpm: Correct the return value in tpm_ibmvtpm_probe()
docs: submitting-patches: Fix crossref to 'The canonical patch format'
NFSD: Fix possible sleep during nfsd4_release_lockowner()
bpf: Enlarge offset check value to INT_MAX in bpf_skb_{load,store}_bytes
Linux 4.14.282
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ieb45fbca1afbc9bf3a97a5beda24be2f82b65abe
commit 45969b4152c1752089351cd6836a42a566d49bcf upstream.
The data length of skb frags + frag_list may be greater than 0xffff, and
skb_header_pointer can not handle negative offset. So, here INT_MAX is used
to check the validity of offset. Add the same change to the related function
skb_store_bytes.
Fixes: 05c74e5e53f6 ("bpf: add bpf_skb_load_bytes helper")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220416105801.88708-2-liujian56@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ce3c4ad7f4ce5db7b4f08a1e237d8dd94b39180b upstream.
nfsd4_release_lockowner() holds clp->cl_lock when it calls
check_for_locks(). However, check_for_locks() calls nfsd_file_get()
/ nfsd_file_put() to access the backing inode's flc_posix list, and
nfsd_file_put() can sleep if the inode was recently removed.
Let's instead rely on the stateowner's reference count to gate
whether the release is permitted. This should be a reliable
indication of locks-in-use since file lock operations and
->lm_get_owner take appropriate references, which are released
appropriately when file locks are removed.
Reported-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6d5aa418b3bd42cdccc36e94ee199af423ef7c84 upstream.
The reference to `explicit_in_reply_to` is pointless as when the
reference was added in the form of "#15" [1], Section 15) was "The
canonical patch format".
The reference of "#15" had not been properly updated in a couple of
reorganizations during the plain-text SubmittingPatches era.
Fix it by using `the_canonical_patch_format`.
[1]: 2ae19acaa50a ("Documentation: Add "how to write a good patch summary" to SubmittingPatches")
Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
Fixes: 5903019b2a5e ("Documentation/SubmittingPatches: convert it to ReST markup")
Fixes: 9b2c76777acc ("Documentation/SubmittingPatches: enrich the Sphinx output")
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: stable@vger.kernel.org # v4.9+
Link: https://lore.kernel.org/r/64e105a5-50be-23f2-6cae-903a2ea98e18@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d0dc1a7100f19121f6e7450f9cdda11926aa3838 upstream.
Currently it returns zero when CRQ response timed out, it should return
an error code instead.
Fixes: d8d74ea3c002 ("tpm: ibmvtpm: Wait for buffer to be set before proceeding")
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4caae58406f8ceb741603eee460d79bacca9b1b5 upstream.
The device-mapper framework provides a mechanism to mark targets as
immutable (and hence fail table reloads that try to change the target
type). Add the DM_TARGET_IMMUTABLE flag to the dm-verity target's
feature flags to prevent switching the verity target with a different
target type.
Fixes: a4ffc152198e ("dm: add verity target")
Cc: stable@vger.kernel.org
Signed-off-by: Sarthak Kukreti <sarthakkukreti@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bfe2b0146c4d0230b68f5c71a64380ff8d361f8b upstream.
dm-stats can be used with a very large number of entries (it is only
limited by 1/4 of total system memory), so add rescheduling points to
the loops that iterate over the entries.
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 567dd8f34560fa221a6343729474536aa7ede4fd upstream.
The device mapper dm-crypt target is using scnprintf("%02x", cc->key[i]) to
report the current key to userspace. However, this is not a constant-time
operation and it may leak information about the key via timing, via cache
access patterns or via the branch predictor.
Change dm-crypt's key printing to use "%c" instead of "%02x". Also
introduce hex2asc() that carefully avoids any branching or memory
accesses when converting a number in the range 0 ... 15 to an ascii
character.
Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Tested-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d3f2a14b8906df913cb04a706367b012db94a6e8 upstream.
The "r" variable shadows an earlier "r" that has function scope. It
means that we accidentally return success instead of an error code.
Smatch has a warning for this:
drivers/md/dm-integrity.c:4503 dm_integrity_ctr()
warn: missing error code 'r'
Fixes: 7eada909bfd7 ("dm: add integrity target")
Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2505a981114dcb715f8977b8433f7540854851d8 upstream.
The asynchronous zspage free worker tries to lock a zspage's entire page
list without defending against page migration. Since pages which haven't
yet been locked can concurrently migrate off the zspage page list while
lock_zspage() churns away, lock_zspage() can suffer from a few different
lethal races.
It can lock a page which no longer belongs to the zspage and unsafely
dereference page_private(), it can unsafely dereference a torn pointer to
the next page (since there's a data race), and it can observe a spurious
NULL pointer to the next page and thus not lock all of the zspage's pages
(since a single page migration will reconstruct the entire page list, and
create_page_chain() unconditionally zeroes out each list pointer in the
process).
Fix the races by using migrate_read_lock() in lock_zspage() to synchronize
with page migration.
Link: https://lkml.kernel.org/r/20220509024703.243847-1-sultan@kerneltoast.com
Fixes: 77ff465799c602 ("zsmalloc: zs_page_migrate: skip unnecessary loops but not return -EBUSY if zspage is not inuse")
Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 56b14ecec97f39118bf85c9ac2438c5a949509ed upstream.
In case the conntrack is clashing, insertion can free skb->_nfct and
set skb->_nfct to the already-confirmed entry.
This wasn't found before because the conntrack entry and the extension
space used to free'd after an rcu grace period, plus the race needs
events enabled to trigger.
Reported-by: <syzbot+793a590957d9c1b96620@syzkaller.appspotmail.com>
Fixes: 71d8c47fc653 ("netfilter: conntrack: introduce clash resolution on insertion race")
Fixes: 2ad9d7747c10 ("netfilter: conntrack: free extension area immediately")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dcd46d897adb70d63e025f175a00a89797d31a43 upstream.
Quoting[1] Ariadne Conill:
"In several other operating systems, it is a hard requirement that the
second argument to execve(2) be the name of a program, thus prohibiting
a scenario where argc < 1. POSIX 2017 also recommends this behaviour,
but it is not an explicit requirement[2]:
The argument arg0 should point to a filename string that is
associated with the process being started by one of the exec
functions.
...
Interestingly, Michael Kerrisk opened an issue about this in 2008[3],
but there was no consensus to support fixing this issue then.
Hopefully now that CVE-2021-4034 shows practical exploitative use[4]
of this bug in a shellcode, we can reconsider.
This issue is being tracked in the KSPP issue tracker[5]."
While the initial code searches[6][7] turned up what appeared to be
mostly corner case tests, trying to that just reject argv == NULL
(or an immediately terminated pointer list) quickly started tripping[8]
existing userspace programs.
The next best approach is forcing a single empty string into argv and
adjusting argc to match. The number of programs depending on argc == 0
seems a smaller set than those calling execve with a NULL argv.
Account for the additional stack space in bprm_stack_limits(). Inject an
empty string when argc == 0 (and set argc = 1). Warn about the case so
userspace has some notice about the change:
process './argc0' launched './argc0' with NULL argv: empty string added
Additionally WARN() and reject NULL argv usage for kernel threads.
[1] https://lore.kernel.org/lkml/20220127000724.15106-1-ariadne@dereferenced.org/
[2] https://pubs.opengroup.org/onlinepubs/9699919799/functions/exec.html
[3] https://bugzilla.kernel.org/show_bug.cgi?id=8408
[4] https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt
[5] https://github.com/KSPP/linux/issues/176
[6] https://codesearch.debian.net/search?q=execve%5C+*%5C%28%5B%5E%2C%5D%2B%2C+*NULL&literal=0
[7] https://codesearch.debian.net/search?q=execlp%3F%5Cs*%5C%28%5B%5E%2C%5D%2B%2C%5Cs*NULL&literal=0
[8] https://lore.kernel.org/lkml/20220131144352.GE16385@xsang-OptiPlex-9020/
Reported-by: Ariadne Conill <ariadne@dereferenced.org>
Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Ariadne Conill <ariadne@dereferenced.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20220201000947.2453721-1-keescook@chromium.org
[vegard: fixed conflicts due to missing
886d7de631da71e30909980fdbf318f7caade262^- and
3950e975431bc914f7e81b8f2a2dbdf2064acb0f^- and
655c16a8ce9c15842547f40ce23fd148aeccc074]
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 336feb502a715909a8136eb6a62a83d7268a353b upstream.
Fix the following -Wstringop-overflow warnings when building with GCC-11:
drivers/gpu/drm/i915/intel_pm.c:3106:9: warning: ‘intel_read_wm_latency’ accessing 16 bytes in a region of size 10 [-Wstringop-overflow=]
3106 | intel_read_wm_latency(dev_priv, dev_priv->wm.pri_latency);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/i915/intel_pm.c:3106:9: note: referencing argument 2 of type ‘u16 *’ {aka ‘short unsigned int *’}
drivers/gpu/drm/i915/intel_pm.c:2861:13: note: in a call to function ‘intel_read_wm_latency’
2861 | static void intel_read_wm_latency(struct drm_i915_private *dev_priv,
| ^~~~~~~~~~~~~~~~~~~~~
by removing the over-specified array size from the argument declarations.
It seems that this code is actually safe because the size of the
array depends on the hardware generation, and the function checks
for that.
Notice that wm can be an array of 5 elements:
drivers/gpu/drm/i915/intel_pm.c:3109: intel_read_wm_latency(dev_priv, dev_priv->wm.pri_latency);
or an array of 8 elements:
drivers/gpu/drm/i915/intel_pm.c:3131: intel_read_wm_latency(dev_priv, dev_priv->wm.skl_latency);
and the compiler legitimately complains about that.
This helps with the ongoing efforts to globally enable
-Wstringop-overflow.
Link: https://github.com/KSPP/linux/issues/181
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d1dc87763f406d4e67caf16dbe438a5647692395 upstream.
A rare BUG_ON triggered in assoc_array_gc:
[3430308.818153] kernel BUG at lib/assoc_array.c:1609!
Which corresponded to the statement currently at line 1593 upstream:
BUG_ON(assoc_array_ptr_is_meta(p));
Using the data from the core dump, I was able to generate a userspace
reproducer[1] and determine the cause of the bug.
[1]: https://github.com/brenns10/kernel_stuff/tree/master/assoc_array_gc
After running the iterator on the entire branch, an internal tree node
looked like the following:
NODE (nr_leaves_on_branch: 3)
SLOT [0] NODE (2 leaves)
SLOT [1] NODE (1 leaf)
SLOT [2..f] NODE (empty)
In the userspace reproducer, the pr_devel output when compressing this
node was:
-- compress node 0x5607cc089380 --
free=0, leaves=0
[0] retain node 2/1 [nx 0]
[1] fold node 1/1 [nx 0]
[2] fold node 0/1 [nx 2]
[3] fold node 0/2 [nx 2]
[4] fold node 0/3 [nx 2]
[5] fold node 0/4 [nx 2]
[6] fold node 0/5 [nx 2]
[7] fold node 0/6 [nx 2]
[8] fold node 0/7 [nx 2]
[9] fold node 0/8 [nx 2]
[10] fold node 0/9 [nx 2]
[11] fold node 0/10 [nx 2]
[12] fold node 0/11 [nx 2]
[13] fold node 0/12 [nx 2]
[14] fold node 0/13 [nx 2]
[15] fold node 0/14 [nx 2]
after: 3
At slot 0, an internal node with 2 leaves could not be folded into the
node, because there was only one available slot (slot 0). Thus, the
internal node was retained. At slot 1, the node had one leaf, and was
able to be folded in successfully. The remaining nodes had no leaves,
and so were removed. By the end of the compression stage, there were 14
free slots, and only 3 leaf nodes. The tree was ascended and then its
parent node was compressed. When this node was seen, it could not be
folded, due to the internal node it contained.
The invariant for compression in this function is: whenever
nr_leaves_on_branch < ASSOC_ARRAY_FAN_OUT, the node should contain all
leaf nodes. The compression step currently cannot guarantee this, given
the corner case shown above.
To fix this issue, retry compression whenever we have retained a node,
and yet nr_leaves_on_branch < ASSOC_ARRAY_FAN_OUT. This second
compression will then allow the node in slot 1 to be folded in,
satisfying the invariant. Below is the output of the reproducer once the
fix is applied:
-- compress node 0x560e9c562380 --
free=0, leaves=0
[0] retain node 2/1 [nx 0]
[1] fold node 1/1 [nx 0]
[2] fold node 0/1 [nx 2]
[3] fold node 0/2 [nx 2]
[4] fold node 0/3 [nx 2]
[5] fold node 0/4 [nx 2]
[6] fold node 0/5 [nx 2]
[7] fold node 0/6 [nx 2]
[8] fold node 0/7 [nx 2]
[9] fold node 0/8 [nx 2]
[10] fold node 0/9 [nx 2]
[11] fold node 0/10 [nx 2]
[12] fold node 0/11 [nx 2]
[13] fold node 0/12 [nx 2]
[14] fold node 0/13 [nx 2]
[15] fold node 0/14 [nx 2]
internal nodes remain despite enough space, retrying
-- compress node 0x560e9c562380 --
free=14, leaves=1
[0] fold node 2/15 [nx 0]
after: 3
Changes
=======
DH:
- Use false instead of 0.
- Reorder the inserted lines in a couple of places to put retained before
next_slot.
ver #2)
- Fix typo in pr_devel, correct comparison to "<="
Fixes: 3cb989501c26 ("Add a generic associative array implementation.")
Cc: <stable@vger.kernel.org>
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Andrew Morton <akpm@linux-foundation.org>
cc: keyrings@vger.kernel.org
Link: https://lore.kernel.org/r/20220511225517.407935-1-stephen.s.brennan@oracle.com/ # v1
Link: https://lore.kernel.org/r/20220512215045.489140-1-stephen.s.brennan@oracle.com/ # v2
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 03a35bc856ddc09f2cc1f4701adecfbf3b464cb3 ]
Due to i2c->adap.dev.fwnode not being set, ACPI_COMPANION() wasn't properly
found for TWSI controllers.
Signed-off-by: Szymon Balcerak <sbalcerak@marvell.com>
Signed-off-by: Piyush Malgujar <pmalgujar@marvell.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
