<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/include/linux, branch linux-5.15.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>XArray: Add calls to might_alloc()</title>
<updated>2025-08-28T14:24:13+00:00</updated>
<author>
<name>Matthew Wilcox (Oracle)</name>
<email>willy@infradead.org</email>
</author>
<published>2022-07-06T18:51:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=461125e8f46c32b220fac9656ef279e1e5abf740'/>
<id>461125e8f46c32b220fac9656ef279e1e5abf740</id>
<content type='text'>
[ Upstream commit 1dd685c414a7b9fdb3d23aca3aedae84f0b998ae ]

Catch bogus GFP flags deterministically, instead of occasionally
when we actually have to allocate memory.

Reported-by: Nikolay Borisov &lt;nborisov@suse.com&gt;
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Stable-dep-of: 99765233ab42 ("NFS: Fixup allocation flags for nfsiod's __GFP_NORETRY")
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 1dd685c414a7b9fdb3d23aca3aedae84f0b998ae ]

Catch bogus GFP flags deterministically, instead of occasionally
when we actually have to allocate memory.

Reported-by: Nikolay Borisov &lt;nborisov@suse.com&gt;
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Stable-dep-of: 99765233ab42 ("NFS: Fixup allocation flags for nfsiod's __GFP_NORETRY")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools: move alignment-related macros to new &lt;linux/align.h&gt;</title>
<updated>2024-09-04T11:23:37+00:00</updated>
<author>
<name>Alexander Lobakin</name>
<email>aleksander.lobakin@intel.com</email>
</author>
<published>2024-03-27T15:23:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ce0aa899c9099a1ba3bbc8a23d543d06973b51a4'/>
<id>ce0aa899c9099a1ba3bbc8a23d543d06973b51a4</id>
<content type='text'>
commit 10a04ff09bcc39e0044190ffe9f00f998f13647c upstream.

Currently, tools have *ALIGN*() macros scattered across the unrelated
headers, as there are only 3 of them and they were added separately
each time on an as-needed basis.
Anyway, let's make it more consistent with the kernel headers and allow
using those macros outside of the mentioned headers. Create
&lt;linux/align.h&gt; inside the tools/ folder and include it where needed.

Signed-off-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 10a04ff09bcc39e0044190ffe9f00f998f13647c upstream.

Currently, tools have *ALIGN*() macros scattered across the unrelated
headers, as there are only 3 of them and they were added separately
each time on an as-needed basis.
Anyway, let's make it more consistent with the kernel headers and allow
using those macros outside of the mentioned headers. Create
&lt;linux/align.h&gt; inside the tools/ folder and include it where needed.

Signed-off-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>bitmap: introduce generic optimized bitmap_size()</title>
<updated>2024-09-04T11:23:16+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=0f00902172b26d756c43c62968affae74fe0bde4'/>
<id>0f00902172b26d756c43c62968affae74fe0bde4</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: Fix BTF_ID symbol generation collision in tools/</title>
<updated>2023-10-06T11:18:23+00:00</updated>
<author>
<name>Nick Desaulniers</name>
<email>ndesaulniers@google.com</email>
</author>
<published>2023-09-15T17:34:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=132a5ae4136b3f244bfc55589bee6eddc234e569'/>
<id>132a5ae4136b3f244bfc55589bee6eddc234e569</id>
<content type='text'>
commit c0bb9fb0e52a64601d38b3739b729d9138d4c8a1 upstream.

Marcus and Satya reported an issue where BTF_ID macro generates same
symbol in separate objects and that breaks final vmlinux link.

  ld.lld: error: ld-temp.o &lt;inline asm&gt;:14577:1: symbol
  '__BTF_ID__struct__cgroup__624' is already defined

This can be triggered under specific configs when __COUNTER__ happens to
be the same for the same symbol in two different translation units,
which is already quite unlikely to happen.

Add __LINE__ number suffix to make BTF_ID symbol more unique, which is
not a complete fix, but it would help for now and meanwhile we can work
on better solution as suggested by Andrii.

Cc: stable@vger.kernel.org
Reported-by: Satya Durga Srinivasu Prabhala &lt;quic_satyap@quicinc.com&gt;
Reported-by: Marcus Seyfarth &lt;m.seyfarth@gmail.com&gt;
Closes: https://github.com/ClangBuiltLinux/linux/issues/1913
Debugged-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Co-developed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/bpf/CAEf4Bzb5KQ2_LmhN769ifMeSJaWfebccUasQOfQKaOd0nQ51tw@mail.gmail.com/
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Link: https://lore.kernel.org/r/20230915-bpf_collision-v3-2-263fc519c21f@google.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.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 c0bb9fb0e52a64601d38b3739b729d9138d4c8a1 upstream.

Marcus and Satya reported an issue where BTF_ID macro generates same
symbol in separate objects and that breaks final vmlinux link.

  ld.lld: error: ld-temp.o &lt;inline asm&gt;:14577:1: symbol
  '__BTF_ID__struct__cgroup__624' is already defined

This can be triggered under specific configs when __COUNTER__ happens to
be the same for the same symbol in two different translation units,
which is already quite unlikely to happen.

Add __LINE__ number suffix to make BTF_ID symbol more unique, which is
not a complete fix, but it would help for now and meanwhile we can work
on better solution as suggested by Andrii.

Cc: stable@vger.kernel.org
Reported-by: Satya Durga Srinivasu Prabhala &lt;quic_satyap@quicinc.com&gt;
Reported-by: Marcus Seyfarth &lt;m.seyfarth@gmail.com&gt;
Closes: https://github.com/ClangBuiltLinux/linux/issues/1913
Debugged-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Co-developed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/bpf/CAEf4Bzb5KQ2_LmhN769ifMeSJaWfebccUasQOfQKaOd0nQ51tw@mail.gmail.com/
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Link: https://lore.kernel.org/r/20230915-bpf_collision-v3-2-263fc519c21f@google.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/ibt: Add ANNOTATE_NOENDBR</title>
<updated>2023-08-26T12:23:39+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2022-03-08T15:30:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f624ce6c7fc27468cb52623222ed61921822edc0'/>
<id>f624ce6c7fc27468cb52623222ed61921822edc0</id>
<content type='text'>
[ Upstream commit c8c301abeae58ec756b8fcb2178a632bd3c9e284 ]

In order to have objtool warn about code references to !ENDBR
instruction, we need an annotation to allow this for non-control-flow
instances -- consider text range checks, text patching, or return
trampolines etc.

Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Acked-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Link: https://lore.kernel.org/r/20220308154317.578968224@infradead.org
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 c8c301abeae58ec756b8fcb2178a632bd3c9e284 ]

In order to have objtool warn about code references to !ENDBR
instruction, we need an annotation to allow this for non-control-flow
instances -- consider text range checks, text patching, or return
trampolines etc.

Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Acked-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Link: https://lore.kernel.org/r/20220308154317.578968224@infradead.org
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>objtool: Add frame-pointer-specific function ignore</title>
<updated>2023-08-26T12:23:38+00:00</updated>
<author>
<name>Josh Poimboeuf</name>
<email>jpoimboe@redhat.com</email>
</author>
<published>2021-09-14T14:41:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f1171d455d94f15ae70b8965b82c3f039f187a63'/>
<id>f1171d455d94f15ae70b8965b82c3f039f187a63</id>
<content type='text'>
[ Upstream commit e028c4f7ac7ca8c96126fe46c54ab3d56ffe6a66 ]

Add a CONFIG_FRAME_POINTER-specific version of
STACK_FRAME_NON_STANDARD() for the case where a function is
intentionally missing frame pointer setup, but otherwise needs
objtool/ORC coverage when frame pointers are disabled.

Link: https://lkml.kernel.org/r/163163047364.489837.17377799909553689661.stgit@devnote2

Signed-off-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Reviewed-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Tested-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Stable-dep-of: c8c301abeae5 ("x86/ibt: Add ANNOTATE_NOENDBR")
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 e028c4f7ac7ca8c96126fe46c54ab3d56ffe6a66 ]

Add a CONFIG_FRAME_POINTER-specific version of
STACK_FRAME_NON_STANDARD() for the case where a function is
intentionally missing frame pointer setup, but otherwise needs
objtool/ORC coverage when frame pointers are disabled.

Link: https://lkml.kernel.org/r/163163047364.489837.17377799909553689661.stgit@devnote2

Signed-off-by: Josh Poimboeuf &lt;jpoimboe@redhat.com&gt;
Reviewed-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Tested-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Stable-dep-of: c8c301abeae5 ("x86/ibt: Add ANNOTATE_NOENDBR")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools: fix ARRAY_SIZE defines in tools and selftests hdrs</title>
<updated>2023-02-06T06:59:01+00:00</updated>
<author>
<name>Shuah Khan</name>
<email>skhan@linuxfoundation.org</email>
</author>
<published>2021-12-08T17:47:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c9e52db90031b7a89bf667057df5ca9c25cd68ff'/>
<id>c9e52db90031b7a89bf667057df5ca9c25cd68ff</id>
<content type='text'>
commit 066b34aa5461f6072dbbecb690f4fe446b736ebf upstream.

tools/include/linux/kernel.h and kselftest_harness.h are missing
ifndef guard around ARRAY_SIZE define. Fix them to avoid duplicate
define errors during compile when another file defines it. This
problem was found when compiling selftests that include a header
with ARRAY_SIZE define.

ARRAY_SIZE is defined in several selftests. There are about 25+
duplicate defines in various selftests source and header files.
Add ARRAY_SIZE to kselftest.h in preparation for removing duplicate
ARRAY_SIZE defines from individual test files.

Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Cc: Kyle Huey &lt;me@kylehuey.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 066b34aa5461f6072dbbecb690f4fe446b736ebf upstream.

tools/include/linux/kernel.h and kselftest_harness.h are missing
ifndef guard around ARRAY_SIZE define. Fix them to avoid duplicate
define errors during compile when another file defines it. This
problem was found when compiling selftests that include a header
with ARRAY_SIZE define.

ARRAY_SIZE is defined in several selftests. There are about 25+
duplicate defines in various selftests source and header files.
Add ARRAY_SIZE to kselftest.h in preparation for removing duplicate
ARRAY_SIZE defines from individual test files.

Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Cc: Kyle Huey &lt;me@kylehuey.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools/include: Add _RET_IP_ and math definitions to kernel.h</title>
<updated>2022-12-31T12:14:44+00:00</updated>
<author>
<name>Karolina Drobnik</name>
<email>karolinadrobnik@gmail.com</email>
</author>
<published>2022-12-23T00:09:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6215904fe29537067ff938fae1732b204abf8ea7'/>
<id>6215904fe29537067ff938fae1732b204abf8ea7</id>
<content type='text'>
commit 5cf67a6051ea2558fd7c3d39c5a808db73073e9d upstream.

Add max_t, min_t and clamp functions, together with _RET_IP_
definition, so they can be used in testing.

Signed-off-by: Karolina Drobnik &lt;karolinadrobnik@gmail.com&gt;
Signed-off-by: Mike Rapoport &lt;rppt@kernel.org&gt;
Link: https://lore.kernel.org/r/230fea382cb1e1659cdd52a55201854d38a0a149.1643796665.git.karolinadrobnik@gmail.com
[tyhicks: Backport around contextual differences due to the lack of v5.16 commit
 d6e6a27d960f ("tools: Fix math.h breakage"). That commit fixed a commit
 that was merged in v5.16-rc1 and, therefore, doesn't need to go back to
 the stable branches.]
Signed-off-by: Tyler Hicks (Microsoft) &lt;code@tyhicks.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5cf67a6051ea2558fd7c3d39c5a808db73073e9d upstream.

Add max_t, min_t and clamp functions, together with _RET_IP_
definition, so they can be used in testing.

Signed-off-by: Karolina Drobnik &lt;karolinadrobnik@gmail.com&gt;
Signed-off-by: Mike Rapoport &lt;rppt@kernel.org&gt;
Link: https://lore.kernel.org/r/230fea382cb1e1659cdd52a55201854d38a0a149.1643796665.git.karolinadrobnik@gmail.com
[tyhicks: Backport around contextual differences due to the lack of v5.16 commit
 d6e6a27d960f ("tools: Fix math.h breakage"). That commit fixed a commit
 that was merged in v5.16-rc1 and, therefore, doesn't need to go back to
 the stable branches.]
Signed-off-by: Tyler Hicks (Microsoft) &lt;code@tyhicks.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>objtool: Re-add UNWIND_HINT_{SAVE_RESTORE}</title>
<updated>2022-07-23T10:54:08+00:00</updated>
<author>
<name>Josh Poimboeuf</name>
<email>jpoimboe@kernel.org</email>
</author>
<published>2022-06-24T10:52:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c590fa2d2dac50e9e1ea6946506636617b2f8694'/>
<id>c590fa2d2dac50e9e1ea6946506636617b2f8694</id>
<content type='text'>
commit 8faea26e611189e933ea2281975ff4dc7c1106b6 upstream.

Commit

  c536ed2fffd5 ("objtool: Remove SAVE/RESTORE hints")

removed the save/restore unwind hints because they were no longer
needed. Now they're going to be needed again so re-add them.

Signed-off-by: Josh Poimboeuf &lt;jpoimboe@kernel.org&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Signed-off-by: Thadeu Lima de Souza Cascardo &lt;cascardo@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
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<pre>
commit 8faea26e611189e933ea2281975ff4dc7c1106b6 upstream.

Commit

  c536ed2fffd5 ("objtool: Remove SAVE/RESTORE hints")

removed the save/restore unwind hints because they were no longer
needed. Now they're going to be needed again so re-add them.

Signed-off-by: Josh Poimboeuf &lt;jpoimboe@kernel.org&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Signed-off-by: Thadeu Lima de Souza Cascardo &lt;cascardo@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
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</entry>
<entry>
<title>objtool: Add entry UNRET validation</title>
<updated>2022-07-23T10:54:06+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2022-06-14T21:16:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dab72c3c32ccde4f362fff993759b0133448d394'/>
<id>dab72c3c32ccde4f362fff993759b0133448d394</id>
<content type='text'>
commit a09a6e2399ba0595c3042b3164f3ca68a3cff33e upstream.

Since entry asm is tricky, add a validation pass that ensures the
retbleed mitigation has been done before the first actual RET
instruction.

Entry points are those that either have UNWIND_HINT_ENTRY, which acts
as UNWIND_HINT_EMPTY but marks the instruction as an entry point, or
those that have UWIND_HINT_IRET_REGS at +0.

This is basically a variant of validate_branch() that is
intra-function and it will simply follow all branches from marked
entry points and ensures that all paths lead to ANNOTATE_UNRET_END.

If a path hits RET or an indirection the path is a fail and will be
reported.

There are 3 ANNOTATE_UNRET_END instances:

 - UNTRAIN_RET itself
 - exception from-kernel; this path doesn't need UNTRAIN_RET
 - all early exceptions; these also don't need UNTRAIN_RET

Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Reviewed-by: Josh Poimboeuf &lt;jpoimboe@kernel.org&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
[cascardo: tools/objtool/builtin-check.c no link option validation]
[cascardo: tools/objtool/check.c opts.ibt is ibt]
[cascardo: tools/objtool/include/objtool/builtin.h leave unret option as bool, no struct opts]
[cascardo: objtool is still called from scripts/link-vmlinux.sh]
[cascardo: no IBT support]
Signed-off-by: Thadeu Lima de Souza Cascardo &lt;cascardo@canonical.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 a09a6e2399ba0595c3042b3164f3ca68a3cff33e upstream.

Since entry asm is tricky, add a validation pass that ensures the
retbleed mitigation has been done before the first actual RET
instruction.

Entry points are those that either have UNWIND_HINT_ENTRY, which acts
as UNWIND_HINT_EMPTY but marks the instruction as an entry point, or
those that have UWIND_HINT_IRET_REGS at +0.

This is basically a variant of validate_branch() that is
intra-function and it will simply follow all branches from marked
entry points and ensures that all paths lead to ANNOTATE_UNRET_END.

If a path hits RET or an indirection the path is a fail and will be
reported.

There are 3 ANNOTATE_UNRET_END instances:

 - UNTRAIN_RET itself
 - exception from-kernel; this path doesn't need UNTRAIN_RET
 - all early exceptions; these also don't need UNTRAIN_RET

Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Reviewed-by: Josh Poimboeuf &lt;jpoimboe@kernel.org&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
[cascardo: tools/objtool/builtin-check.c no link option validation]
[cascardo: tools/objtool/check.c opts.ibt is ibt]
[cascardo: tools/objtool/include/objtool/builtin.h leave unret option as bool, no struct opts]
[cascardo: objtool is still called from scripts/link-vmlinux.sh]
[cascardo: no IBT support]
Signed-off-by: Thadeu Lima de Souza Cascardo &lt;cascardo@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
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