<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/include/linux, branch v4.19.322</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>ring-buffer: Rename ring_buffer_read() to read_buffer_iter_advance()</title>
<updated>2024-09-12T09:02:55+00:00</updated>
<author>
<name>Steven Rostedt (VMware)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2020-03-17T21:32:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ac8ffa21dde0c1edcd9dd98b5555a0aa4eea3b1f'/>
<id>ac8ffa21dde0c1edcd9dd98b5555a0aa4eea3b1f</id>
<content type='text'>
[ Upstream commit bc1a72afdc4a91844928831cac85731566e03bc6 ]

When the ring buffer was first created, the iterator followed the normal
producer/consumer operations where it had both a peek() operation, that just
returned the event at the current location, and a read(), that would return
the event at the current location and also increment the iterator such that
the next peek() or read() will return the next event.

The only use of the ring_buffer_read() is currently to move the iterator to
the next location and nothing now actually reads the event it returns.
Rename this function to its actual use case to ring_buffer_iter_advance(),
which also adds the "iter" part to the name, which is more meaningful. As
the timestamp returned by ring_buffer_read() was never used, there's no
reason that this new version should bother having returning it. It will also
become a void function.

Link: http://lkml.kernel.org/r/20200317213416.018928618@goodmis.org

Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Stable-dep-of: 49aa8a1f4d68 ("tracing: Avoid possible softlockup in tracing_iter_reset()")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit bc1a72afdc4a91844928831cac85731566e03bc6 ]

When the ring buffer was first created, the iterator followed the normal
producer/consumer operations where it had both a peek() operation, that just
returned the event at the current location, and a read(), that would return
the event at the current location and also increment the iterator such that
the next peek() or read() will return the next event.

The only use of the ring_buffer_read() is currently to move the iterator to
the next location and nothing now actually reads the event it returns.
Rename this function to its actual use case to ring_buffer_iter_advance(),
which also adds the "iter" part to the name, which is more meaningful. As
the timestamp returned by ring_buffer_read() was never used, there's no
reason that this new version should bother having returning it. It will also
become a void function.

Link: http://lkml.kernel.org/r/20200317213416.018928618@goodmis.org

Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Stable-dep-of: 49aa8a1f4d68 ("tracing: Avoid possible softlockup in tracing_iter_reset()")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fbcon: Prevent that screen size is smaller than font size</title>
<updated>2024-09-04T11:13:08+00:00</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2024-08-29T16:14:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=54eaaac622d4547b4abae7e44763b29fa0687132'/>
<id>54eaaac622d4547b4abae7e44763b29fa0687132</id>
<content type='text'>
commit e64242caef18b4a5840b0e7a9bff37abd4f4f933 upstream.

We need to prevent that users configure a screen size which is smaller than the
currently selected font size. Otherwise rendering chars on the screen will
access memory outside the graphics memory region.

This patch adds a new function fbcon_modechange_possible() which
implements this check and which later may be extended with other checks
if necessary.  The new function is called from the FBIOPUT_VSCREENINFO
ioctl handler in fbmem.c, which will return -EINVAL if userspace asked
for a too small screen size.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Hugo SIMELIERE &lt;hsimeliere.opensource@witekio.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e64242caef18b4a5840b0e7a9bff37abd4f4f933 upstream.

We need to prevent that users configure a screen size which is smaller than the
currently selected font size. Otherwise rendering chars on the screen will
access memory outside the graphics memory region.

This patch adds a new function fbcon_modechange_possible() which
implements this check and which later may be extended with other checks
if necessary.  The new function is called from the FBIOPUT_VSCREENINFO
ioctl handler in fbmem.c, which will return -EINVAL if userspace asked
for a too small screen size.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Hugo SIMELIERE &lt;hsimeliere.opensource@witekio.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>block: use "unsigned long" for blk_validate_block_size().</title>
<updated>2024-09-04T11:13:04+00:00</updated>
<author>
<name>Tetsuo Handa</name>
<email>penguin-kernel@i-love.sakura.ne.jp</email>
</author>
<published>2021-12-18T09:41:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ee12aa483f6c8cecbd5a4c794867fee0e068b822'/>
<id>ee12aa483f6c8cecbd5a4c794867fee0e068b822</id>
<content type='text'>
commit 37ae5a0f5287a52cf51242e76ccf198d02ffe495 upstream.

Since lo_simple_ioctl(LOOP_SET_BLOCK_SIZE) and ioctl(NBD_SET_BLKSIZE) pass
user-controlled "unsigned long arg" to blk_validate_block_size(),
"unsigned long" should be used for validation.

Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://lore.kernel.org/r/9ecbf057-4375-c2db-ab53-e4cc0dff953d@i-love.sakura.ne.jp
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: David Hunter &lt;david.hunter.linux@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 37ae5a0f5287a52cf51242e76ccf198d02ffe495 upstream.

Since lo_simple_ioctl(LOOP_SET_BLOCK_SIZE) and ioctl(NBD_SET_BLKSIZE) pass
user-controlled "unsigned long arg" to blk_validate_block_size(),
"unsigned long" should be used for validation.

Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Link: https://lore.kernel.org/r/9ecbf057-4375-c2db-ab53-e4cc0dff953d@i-love.sakura.ne.jp
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: David Hunter &lt;david.hunter.linux@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>overflow: Implement size_t saturating arithmetic helpers</title>
<updated>2024-09-04T11:13:00+00:00</updated>
<author>
<name>Kees Cook</name>
<email>keescook@chromium.org</email>
</author>
<published>2021-09-18T22:17:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=1f5cbd78177975aece64bb132948f611af2359c0'/>
<id>1f5cbd78177975aece64bb132948f611af2359c0</id>
<content type='text'>
commit e1be43d9b5d0d1310dbd90185a8e5c7145dde40f upstream.

In order to perform more open-coded replacements of common allocation
size arithmetic, the kernel needs saturating (SIZE_MAX) helpers for
multiplication, addition, and subtraction. For example, it is common in
allocators, especially on realloc, to add to an existing size:

    p = krealloc(map-&gt;patch,
                 sizeof(struct reg_sequence) * (map-&gt;patch_regs + num_regs),
                 GFP_KERNEL);

There is no existing saturating replacement for this calculation, and
just leaving the addition open coded inside array_size() could
potentially overflow as well. For example, an overflow in an expression
for a size_t argument might wrap to zero:

    array_size(anything, something_at_size_max + 1) == 0

Introduce size_mul(), size_add(), and size_sub() helpers that
implicitly promote arguments to size_t and saturated calculations for
use in allocations. With these helpers it is also possible to redefine
array_size(), array3_size(), flex_array_size(), and struct_size() in
terms of the new helpers.

As with the check_*_overflow() helpers, the new helpers use __must_check,
though what is really desired is a way to make sure that assignment is
only to a size_t lvalue. Without this, it's still possible to introduce
overflow/underflow via type conversion (i.e. from size_t to int).
Enforcing this will currently need to be left to static analysis or
future use of -Wconversion.

Additionally update the overflow unit tests to force runtime evaluation
for the pathological cases.

Cc: Rasmus Villemoes &lt;linux@rasmusvillemoes.dk&gt;
Cc: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Jason Gunthorpe &lt;jgg@ziepe.ca&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Keith Busch &lt;kbusch@kernel.org&gt;
Cc: Len Baker &lt;len.baker@gmx.com&gt;
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e1be43d9b5d0d1310dbd90185a8e5c7145dde40f upstream.

In order to perform more open-coded replacements of common allocation
size arithmetic, the kernel needs saturating (SIZE_MAX) helpers for
multiplication, addition, and subtraction. For example, it is common in
allocators, especially on realloc, to add to an existing size:

    p = krealloc(map-&gt;patch,
                 sizeof(struct reg_sequence) * (map-&gt;patch_regs + num_regs),
                 GFP_KERNEL);

There is no existing saturating replacement for this calculation, and
just leaving the addition open coded inside array_size() could
potentially overflow as well. For example, an overflow in an expression
for a size_t argument might wrap to zero:

    array_size(anything, something_at_size_max + 1) == 0

Introduce size_mul(), size_add(), and size_sub() helpers that
implicitly promote arguments to size_t and saturated calculations for
use in allocations. With these helpers it is also possible to redefine
array_size(), array3_size(), flex_array_size(), and struct_size() in
terms of the new helpers.

As with the check_*_overflow() helpers, the new helpers use __must_check,
though what is really desired is a way to make sure that assignment is
only to a size_t lvalue. Without this, it's still possible to introduce
overflow/underflow via type conversion (i.e. from size_t to int).
Enforcing this will currently need to be left to static analysis or
future use of -Wconversion.

Additionally update the overflow unit tests to force runtime evaluation
for the pathological cases.

Cc: Rasmus Villemoes &lt;linux@rasmusvillemoes.dk&gt;
Cc: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Cc: Nathan Chancellor &lt;nathan@kernel.org&gt;
Cc: Jason Gunthorpe &lt;jgg@ziepe.ca&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Keith Busch &lt;kbusch@kernel.org&gt;
Cc: Len Baker &lt;len.baker@gmx.com&gt;
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>overflow.h: Add flex_array_size() helper</title>
<updated>2024-09-04T11:12:59+00:00</updated>
<author>
<name>Gustavo A. R. Silva</name>
<email>gustavoars@kernel.org</email>
</author>
<published>2020-06-09T01:22:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=81bec94f5d864318fa4fccfd06e5449c501885b7'/>
<id>81bec94f5d864318fa4fccfd06e5449c501885b7</id>
<content type='text'>
commit b19d57d0f3cc6f1022edf94daf1d70506a09e3c2 upstream.

Add flex_array_size() helper for the calculation of the size, in bytes,
of a flexible array member contained within an enclosing structure.

Example of usage:

struct something {
	size_t count;
	struct foo items[];
};

struct something *instance;

instance = kmalloc(struct_size(instance, items, count), GFP_KERNEL);
instance-&gt;count = count;
memcpy(instance-&gt;items, src, flex_array_size(instance, items, instance-&gt;count));

The helper returns SIZE_MAX on overflow instead of wrapping around.

Additionally replaces parameter "n" with "count" in struct_size() helper
for greater clarity and unification.

Signed-off-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Link: https://lore.kernel.org/r/20200609012233.GA3371@embeddedor
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b19d57d0f3cc6f1022edf94daf1d70506a09e3c2 upstream.

Add flex_array_size() helper for the calculation of the size, in bytes,
of a flexible array member contained within an enclosing structure.

Example of usage:

struct something {
	size_t count;
	struct foo items[];
};

struct something *instance;

instance = kmalloc(struct_size(instance, items, count), GFP_KERNEL);
instance-&gt;count = count;
memcpy(instance-&gt;items, src, flex_array_size(instance, items, instance-&gt;count));

The helper returns SIZE_MAX on overflow instead of wrapping around.

Additionally replaces parameter "n" with "count" in struct_size() helper
for greater clarity and unification.

Signed-off-by: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Link: https://lore.kernel.org/r/20200609012233.GA3371@embeddedor
Signed-off-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fix bitmap corruption on close_range() with CLOSE_RANGE_UNSHARE</title>
<updated>2024-09-04T11:12:59+00:00</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2024-08-03T22:02:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ee501f827f3db02d4e599afbbc1a7f8b792d05d7'/>
<id>ee501f827f3db02d4e599afbbc1a7f8b792d05d7</id>
<content type='text'>
commit 9a2fa1472083580b6c66bdaf291f591e1170123a upstream.

copy_fd_bitmaps(new, old, count) is expected to copy the first
count/BITS_PER_LONG bits from old-&gt;full_fds_bits[] and fill
the rest with zeroes.  What it does is copying enough words
(BITS_TO_LONGS(count/BITS_PER_LONG)), then memsets the rest.
That works fine, *if* all bits past the cutoff point are
clear.  Otherwise we are risking garbage from the last word
we'd copied.

For most of the callers that is true - expand_fdtable() has
count equal to old-&gt;max_fds, so there's no open descriptors
past count, let alone fully occupied words in -&gt;open_fds[],
which is what bits in -&gt;full_fds_bits[] correspond to.

The other caller (dup_fd()) passes sane_fdtable_size(old_fdt, max_fds),
which is the smallest multiple of BITS_PER_LONG that covers all
opened descriptors below max_fds.  In the common case (copying on
fork()) max_fds is ~0U, so all opened descriptors will be below
it and we are fine, by the same reasons why the call in expand_fdtable()
is safe.

Unfortunately, there is a case where max_fds is less than that
and where we might, indeed, end up with junk in -&gt;full_fds_bits[] -
close_range(from, to, CLOSE_RANGE_UNSHARE) with
	* descriptor table being currently shared
	* 'to' being above the current capacity of descriptor table
	* 'from' being just under some chunk of opened descriptors.
In that case we end up with observably wrong behaviour - e.g. spawn
a child with CLONE_FILES, get all descriptors in range 0..127 open,
then close_range(64, ~0U, CLOSE_RANGE_UNSHARE) and watch dup(0) ending
up with descriptor #128, despite #64 being observably not open.

The minimally invasive fix would be to deal with that in dup_fd().
If this proves to add measurable overhead, we can go that way, but
let's try to fix copy_fd_bitmaps() first.

* new helper: bitmap_copy_and_expand(to, from, bits_to_copy, size).
* make copy_fd_bitmaps() take the bitmap size in words, rather than
bits; it's 'count' argument is always a multiple of BITS_PER_LONG,
so we are not losing any information, and that way we can use the
same helper for all three bitmaps - compiler will see that count
is a multiple of BITS_PER_LONG for the large ones, so it'll generate
plain memcpy()+memset().

Reproducer added to tools/testing/selftests/core/close_range_test.c

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9a2fa1472083580b6c66bdaf291f591e1170123a upstream.

copy_fd_bitmaps(new, old, count) is expected to copy the first
count/BITS_PER_LONG bits from old-&gt;full_fds_bits[] and fill
the rest with zeroes.  What it does is copying enough words
(BITS_TO_LONGS(count/BITS_PER_LONG)), then memsets the rest.
That works fine, *if* all bits past the cutoff point are
clear.  Otherwise we are risking garbage from the last word
we'd copied.

For most of the callers that is true - expand_fdtable() has
count equal to old-&gt;max_fds, so there's no open descriptors
past count, let alone fully occupied words in -&gt;open_fds[],
which is what bits in -&gt;full_fds_bits[] correspond to.

The other caller (dup_fd()) passes sane_fdtable_size(old_fdt, max_fds),
which is the smallest multiple of BITS_PER_LONG that covers all
opened descriptors below max_fds.  In the common case (copying on
fork()) max_fds is ~0U, so all opened descriptors will be below
it and we are fine, by the same reasons why the call in expand_fdtable()
is safe.

Unfortunately, there is a case where max_fds is less than that
and where we might, indeed, end up with junk in -&gt;full_fds_bits[] -
close_range(from, to, CLOSE_RANGE_UNSHARE) with
	* descriptor table being currently shared
	* 'to' being above the current capacity of descriptor table
	* 'from' being just under some chunk of opened descriptors.
In that case we end up with observably wrong behaviour - e.g. spawn
a child with CLONE_FILES, get all descriptors in range 0..127 open,
then close_range(64, ~0U, CLOSE_RANGE_UNSHARE) and watch dup(0) ending
up with descriptor #128, despite #64 being observably not open.

The minimally invasive fix would be to deal with that in dup_fd().
If this proves to add measurable overhead, we can go that way, but
let's try to fix copy_fd_bitmaps() first.

* new helper: bitmap_copy_and_expand(to, from, bits_to_copy, size).
* make copy_fd_bitmaps() take the bitmap size in words, rather than
bits; it's 'count' argument is always a multiple of BITS_PER_LONG,
so we are not losing any information, and that way we can use the
same helper for all three bitmaps - compiler will see that count
is a multiple of BITS_PER_LONG for the large ones, so it'll generate
plain memcpy()+memset().

Reproducer added to tools/testing/selftests/core/close_range_test.c

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bitmap: introduce generic optimized bitmap_size()</title>
<updated>2024-09-04T11:12:59+00:00</updated>
<author>
<name>Alexander Lobakin</name>
<email>aleksander.lobakin@intel.com</email>
</author>
<published>2024-03-27T15:23:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=188729977a0cfac6e04a59bf75f85ccd19ad4b4d'/>
<id>188729977a0cfac6e04a59bf75f85ccd19ad4b4d</id>
<content type='text'>
commit a37fbe666c016fd89e4460d0ebfcea05baba46dc upstream.

The number of times yet another open coded
`BITS_TO_LONGS(nbits) * sizeof(long)` can be spotted is huge.
Some generic helper is long overdue.

Add one, bitmap_size(), but with one detail.
BITS_TO_LONGS() uses DIV_ROUND_UP(). The latter works well when both
divident and divisor are compile-time constants or when the divisor
is not a pow-of-2. When it is however, the compilers sometimes tend
to generate suboptimal code (GCC 13):

48 83 c0 3f          	add    $0x3f,%rax
48 c1 e8 06          	shr    $0x6,%rax
48 8d 14 c5 00 00 00 00	lea    0x0(,%rax,8),%rdx

%BITS_PER_LONG is always a pow-2 (either 32 or 64), but GCC still does
full division of `nbits + 63` by it and then multiplication by 8.
Instead of BITS_TO_LONGS(), use ALIGN() and then divide by 8. GCC:

8d 50 3f             	lea    0x3f(%rax),%edx
c1 ea 03             	shr    $0x3,%edx
81 e2 f8 ff ff 1f    	and    $0x1ffffff8,%edx

Now it shifts `nbits + 63` by 3 positions (IOW performs fast division
by 8) and then masks bits[2:0]. bloat-o-meter:

add/remove: 0/0 grow/shrink: 20/133 up/down: 156/-773 (-617)

Clang does it better and generates the same code before/after starting
from -O1, except that with the ALIGN() approach it uses %edx and thus
still saves some bytes:

add/remove: 0/0 grow/shrink: 9/133 up/down: 18/-538 (-520)

Note that we can't expand DIV_ROUND_UP() by adding a check and using
this approach there, as it's used in array declarations where
expressions are not allowed.
Add this helper to tools/ as well.

Reviewed-by: Przemek Kitszel &lt;przemyslaw.kitszel@intel.com&gt;
Acked-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Signed-off-by: Alexander Lobakin &lt;aleksander.lobakin@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a37fbe666c016fd89e4460d0ebfcea05baba46dc upstream.

The number of times yet another open coded
`BITS_TO_LONGS(nbits) * sizeof(long)` can be spotted is huge.
Some generic helper is long overdue.

Add one, bitmap_size(), but with one detail.
BITS_TO_LONGS() uses DIV_ROUND_UP(). The latter works well when both
divident and divisor are compile-time constants or when the divisor
is not a pow-of-2. When it is however, the compilers sometimes tend
to generate suboptimal code (GCC 13):

48 83 c0 3f          	add    $0x3f,%rax
48 c1 e8 06          	shr    $0x6,%rax
48 8d 14 c5 00 00 00 00	lea    0x0(,%rax,8),%rdx

%BITS_PER_LONG is always a pow-2 (either 32 or 64), but GCC still does
full division of `nbits + 63` by it and then multiplication by 8.
Instead of BITS_TO_LONGS(), use ALIGN() and then divide by 8. GCC:

8d 50 3f             	lea    0x3f(%rax),%edx
c1 ea 03             	shr    $0x3,%edx
81 e2 f8 ff ff 1f    	and    $0x1ffffff8,%edx

Now it shifts `nbits + 63` by 3 positions (IOW performs fast division
by 8) and then masks bits[2:0]. bloat-o-meter:

add/remove: 0/0 grow/shrink: 20/133 up/down: 156/-773 (-617)

Clang does it better and generates the same code before/after starting
from -O1, except that with the ALIGN() approach it uses %edx and thus
still saves some bytes:

add/remove: 0/0 grow/shrink: 9/133 up/down: 18/-538 (-520)

Note that we can't expand DIV_ROUND_UP() by adding a check and using
this approach there, as it's used in array declarations where
expressions are not allowed.
Add this helper to tools/ as well.

Reviewed-by: Przemek Kitszel &lt;przemyslaw.kitszel@intel.com&gt;
Acked-by: Yury Norov &lt;yury.norov@gmail.com&gt;
Signed-off-by: Alexander Lobakin &lt;aleksander.lobakin@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: kprobe: remove unused declaring of bpf_kprobe_override</title>
<updated>2024-08-19T03:32:14+00:00</updated>
<author>
<name>Menglong Dong</name>
<email>menglong8.dong@gmail.com</email>
</author>
<published>2024-08-05T05:01:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0b8cf71c2c1b9a6e8f7acd620d8e4b0c24a12920'/>
<id>0b8cf71c2c1b9a6e8f7acd620d8e4b0c24a12920</id>
<content type='text'>
[ Upstream commit 0e8b53979ac86eddb3fd76264025a70071a25574 ]

After the commit 66665ad2f102 ("tracing/kprobe: bpf: Compare instruction
pointer with original one"), "bpf_kprobe_override" is not used anywhere
anymore, and we can remove it now.

Link: https://lore.kernel.org/all/20240710085939.11520-1-dongml2@chinatelecom.cn/

Fixes: 66665ad2f102 ("tracing/kprobe: bpf: Compare instruction pointer with original one")
Signed-off-by: Menglong Dong &lt;dongml2@chinatelecom.cn&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0e8b53979ac86eddb3fd76264025a70071a25574 ]

After the commit 66665ad2f102 ("tracing/kprobe: bpf: Compare instruction
pointer with original one"), "bpf_kprobe_override" is not used anywhere
anymore, and we can remove it now.

Link: https://lore.kernel.org/all/20240710085939.11520-1-dongml2@chinatelecom.cn/

Fixes: 66665ad2f102 ("tracing/kprobe: bpf: Compare instruction pointer with original one")
Signed-off-by: Menglong Dong &lt;dongml2@chinatelecom.cn&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: Add Edimax Vendor ID to pci_ids.h</title>
<updated>2024-08-19T03:32:11+00:00</updated>
<author>
<name>FUJITA Tomonori</name>
<email>fujita.tomonori@gmail.com</email>
</author>
<published>2024-06-23T23:55:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a35a163cd56b583ef698eadef9b856b0fe6e2727'/>
<id>a35a163cd56b583ef698eadef9b856b0fe6e2727</id>
<content type='text'>
[ Upstream commit eee5528890d54b22b46f833002355a5ee94c3bb4 ]

Add the Edimax Vendor ID (0x1432) for an ethernet driver for Tehuti
Networks TN40xx chips. This ID can be used for Realtek 8180 and Ralink
rt28xx wireless drivers.

Signed-off-by: FUJITA Tomonori &lt;fujita.tomonori@gmail.com&gt;
Acked-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Link: https://patch.msgid.link/20240623235507.108147-2-fujita.tomonori@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit eee5528890d54b22b46f833002355a5ee94c3bb4 ]

Add the Edimax Vendor ID (0x1432) for an ethernet driver for Tehuti
Networks TN40xx chips. This ID can be used for Realtek 8180 and Ralink
rt28xx wireless drivers.

Signed-off-by: FUJITA Tomonori &lt;fujita.tomonori@gmail.com&gt;
Acked-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Link: https://patch.msgid.link/20240623235507.108147-2-fujita.tomonori@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>hwmon: Introduce SENSOR_DEVICE_ATTR_{RO, RW, WO} and variants</title>
<updated>2024-08-19T03:31:56+00:00</updated>
<author>
<name>Guenter Roeck</name>
<email>linux@roeck-us.net</email>
</author>
<published>2016-12-27T23:28:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=eb04482acd9870b84970fe1549203fedc1bbcc79'/>
<id>eb04482acd9870b84970fe1549203fedc1bbcc79</id>
<content type='text'>
[ Upstream commit a5c47c0d388b939dd578fd466aa804b7f2445390 ]

Introduce SENSOR_DEVICE_ATTR_{RO,RW,WO} and SENSOR_DEVICE_ATTR_2_{RO,RW,WO}
as simplified variants of SENSOR_DEVICE_ATTR and SENSOR_DEVICE_ATTR_2 to
simplify the source code, improve readbility, and reduce the chance of
inconsistencies.

Signed-off-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Stable-dep-of: 1ea3fd1eb986 ("hwmon: (max6697) Fix swapped temp{1,8} critical alarms")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit a5c47c0d388b939dd578fd466aa804b7f2445390 ]

Introduce SENSOR_DEVICE_ATTR_{RO,RW,WO} and SENSOR_DEVICE_ATTR_2_{RO,RW,WO}
as simplified variants of SENSOR_DEVICE_ATTR and SENSOR_DEVICE_ATTR_2 to
simplify the source code, improve readbility, and reduce the chance of
inconsistencies.

Signed-off-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Stable-dep-of: 1ea3fd1eb986 ("hwmon: (max6697) Fix swapped temp{1,8} critical alarms")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
