<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/x86/kernel, branch v6.18</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'x86-urgent-2025-11-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2025-11-15T16:55:29+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-11-15T16:55:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b8a2c32b22de691cceb835f1de306f2a8c1dd0c8'/>
<id>b8a2c32b22de691cceb835f1de306f2a8c1dd0c8</id>
<content type='text'>
Pull x86 fixes from Ingo Molnar:

 - Update the list of AMD microcode minimum Entrysign revisions

 - Add additional fixed AMD RDSEED microcode revisions

 - Update the language transliteration for Kiryl Shutsemau's name
   in the MAINTAINERS entry

* tag 'x86-urgent-2025-11-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode/AMD: Add Zen5 model 0x44, stepping 0x1 minrev
  x86/CPU/AMD: Add additional fixed RDSEED microcode revisions
  MAINTAINERS: Update name spelling
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 fixes from Ingo Molnar:

 - Update the list of AMD microcode minimum Entrysign revisions

 - Add additional fixed AMD RDSEED microcode revisions

 - Update the language transliteration for Kiryl Shutsemau's name
   in the MAINTAINERS entry

* tag 'x86-urgent-2025-11-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode/AMD: Add Zen5 model 0x44, stepping 0x1 minrev
  x86/CPU/AMD: Add additional fixed RDSEED microcode revisions
  MAINTAINERS: Update name spelling
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf</title>
<updated>2025-11-14T23:39:39+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-11-14T23:39:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=cbba5d1b53fb82209feacb459edecb1ef8427119'/>
<id>cbba5d1b53fb82209feacb459edecb1ef8427119</id>
<content type='text'>
Pull bpf fixes from Alexei Starovoitov:

 - Fix interaction between livepatch and BPF fexit programs (Song Liu)
   With Steven and Masami acks.

 - Fix stack ORC unwind from BPF kprobe_multi (Jiri Olsa)
   With Steven and Masami acks.

 - Fix out of bounds access in widen_imprecise_scalars() in the verifier
   (Eduard Zingerman)

 - Fix conflicts between MPTCP and BPF sockmap (Jiayuan Chen)

 - Fix net_sched storage collision with BPF data_meta/data_end (Eric
   Dumazet)

 - Add _impl suffix to BPF kfuncs with implicit args to avoid breaking
   them in bpf-next when KF_IMPLICIT_ARGS is added (Mykyta Yatsenko)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: Test widen_imprecise_scalars() with different stack depth
  bpf: account for current allocated stack depth in widen_imprecise_scalars()
  bpf: Add bpf_prog_run_data_pointers()
  selftests/bpf: Add mptcp test with sockmap
  mptcp: Fix proto fallback detection with BPF
  mptcp: Disallow MPTCP subflows from sockmap
  selftests/bpf: Add stacktrace ips test for raw_tp
  selftests/bpf: Add stacktrace ips test for kprobe_multi/kretprobe_multi
  x86/fgraph,bpf: Fix stack ORC unwind from kprobe_multi return probe
  Revert "perf/x86: Always store regs-&gt;ip in perf_callchain_kernel()"
  bpf: add _impl suffix for bpf_stream_vprintk() kfunc
  bpf:add _impl suffix for bpf_task_work_schedule* kfuncs
  selftests/bpf: Add tests for livepatch + bpf trampoline
  ftrace: bpf: Fix IPMODIFY + DIRECT in modify_ftrace_direct()
  ftrace: Fix BPF fexit with livepatch
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull bpf fixes from Alexei Starovoitov:

 - Fix interaction between livepatch and BPF fexit programs (Song Liu)
   With Steven and Masami acks.

 - Fix stack ORC unwind from BPF kprobe_multi (Jiri Olsa)
   With Steven and Masami acks.

 - Fix out of bounds access in widen_imprecise_scalars() in the verifier
   (Eduard Zingerman)

 - Fix conflicts between MPTCP and BPF sockmap (Jiayuan Chen)

 - Fix net_sched storage collision with BPF data_meta/data_end (Eric
   Dumazet)

 - Add _impl suffix to BPF kfuncs with implicit args to avoid breaking
   them in bpf-next when KF_IMPLICIT_ARGS is added (Mykyta Yatsenko)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: Test widen_imprecise_scalars() with different stack depth
  bpf: account for current allocated stack depth in widen_imprecise_scalars()
  bpf: Add bpf_prog_run_data_pointers()
  selftests/bpf: Add mptcp test with sockmap
  mptcp: Fix proto fallback detection with BPF
  mptcp: Disallow MPTCP subflows from sockmap
  selftests/bpf: Add stacktrace ips test for raw_tp
  selftests/bpf: Add stacktrace ips test for kprobe_multi/kretprobe_multi
  x86/fgraph,bpf: Fix stack ORC unwind from kprobe_multi return probe
  Revert "perf/x86: Always store regs-&gt;ip in perf_callchain_kernel()"
  bpf: add _impl suffix for bpf_stream_vprintk() kfunc
  bpf:add _impl suffix for bpf_task_work_schedule* kfuncs
  selftests/bpf: Add tests for livepatch + bpf trampoline
  ftrace: bpf: Fix IPMODIFY + DIRECT in modify_ftrace_direct()
  ftrace: Fix BPF fexit with livepatch
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/microcode/AMD: Add Zen5 model 0x44, stepping 0x1 minrev</title>
<updated>2025-11-14T13:04:49+00:00</updated>
<author>
<name>Borislav Petkov (AMD)</name>
<email>bp@alien8.de</email>
</author>
<published>2025-11-14T13:01:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=dd14022a7ce96963aa923e35cf4bcc8c32f95840'/>
<id>dd14022a7ce96963aa923e35cf4bcc8c32f95840</id>
<content type='text'>
Add the minimum Entrysign revision for that model+stepping to the list
of minimum revisions.

Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches")
Reported-by: Andrew Cooper &lt;andrew.cooper3@citrix.com&gt;
Signed-off-by: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: &lt;stable@kernel.org&gt;
Link: https://lore.kernel.org/r/e94dd76b-4911-482f-8500-5c848a3df026@citrix.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add the minimum Entrysign revision for that model+stepping to the list
of minimum revisions.

Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches")
Reported-by: Andrew Cooper &lt;andrew.cooper3@citrix.com&gt;
Signed-off-by: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: &lt;stable@kernel.org&gt;
Link: https://lore.kernel.org/r/e94dd76b-4911-482f-8500-5c848a3df026@citrix.com
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/CPU/AMD: Add additional fixed RDSEED microcode revisions</title>
<updated>2025-11-14T12:02:11+00:00</updated>
<author>
<name>Mario Limonciello</name>
<email>mario.limonciello@amd.com</email>
</author>
<published>2025-11-13T22:35:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e1a97a627cd01d73fac5dd054d8f3de601ef2781'/>
<id>e1a97a627cd01d73fac5dd054d8f3de601ef2781</id>
<content type='text'>
Microcode that resolves the RDSEED failure (SB-7055 [1]) has been released for
additional Zen5 models to linux-firmware [2]. Update the zen5_rdseed_microcode
array to cover these new models.

Fixes: 607b9fb2ce24 ("x86/CPU/AMD: Add RDSEED fix for Zen5")
Signed-off-by: Mario Limonciello &lt;mario.limonciello@amd.com&gt;
Signed-off-by: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: &lt;stable@kernel.org&gt;
Link: https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7055.html [1]
Link: https://gitlab.com/kernel-firmware/linux-firmware/-/commit/6167e5566900cf236f7a69704e8f4c441bc7212a [2]
Link: https://patch.msgid.link/20251113223608.1495655-1-mario.limonciello@amd.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Microcode that resolves the RDSEED failure (SB-7055 [1]) has been released for
additional Zen5 models to linux-firmware [2]. Update the zen5_rdseed_microcode
array to cover these new models.

Fixes: 607b9fb2ce24 ("x86/CPU/AMD: Add RDSEED fix for Zen5")
Signed-off-by: Mario Limonciello &lt;mario.limonciello@amd.com&gt;
Signed-off-by: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: &lt;stable@kernel.org&gt;
Link: https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7055.html [1]
Link: https://gitlab.com/kernel-firmware/linux-firmware/-/commit/6167e5566900cf236f7a69704e8f4c441bc7212a [2]
Link: https://patch.msgid.link/20251113223608.1495655-1-mario.limonciello@amd.com
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'acpi-cppc' and 'acpi-tables'</title>
<updated>2025-11-13T19:40:51+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2025-11-13T19:40:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7564f3543cf19b1232553ab10399c9fbf514b5f3'/>
<id>7564f3543cf19b1232553ab10399c9fbf514b5f3</id>
<content type='text'>
Merge ACPI CPPC library fixes and an ACPI MRRM table parser fix for
6.18-rc6.

* acpi-cppc:
  ACPI: CPPC: Limit perf ctrs in PCC check only to online CPUs
  ACPI: CPPC: Perform fast check switch only for online CPUs
  ACPI: CPPC: Check _CPC validity for only the online CPUs
  ACPI: CPPC: Detect preferred core availability on online CPUs

* acpi-tables:
  ACPI: MRRM: Fix memory leaks and improve error handling
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge ACPI CPPC library fixes and an ACPI MRRM table parser fix for
6.18-rc6.

* acpi-cppc:
  ACPI: CPPC: Limit perf ctrs in PCC check only to online CPUs
  ACPI: CPPC: Perform fast check switch only for online CPUs
  ACPI: CPPC: Check _CPC validity for only the online CPUs
  ACPI: CPPC: Detect preferred core availability on online CPUs

* acpi-tables:
  ACPI: MRRM: Fix memory leaks and improve error handling
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'x86-urgent-2025-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2025-11-08T17:01:11+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-11-08T17:01:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0d7bee10beeb59b1133bf5a4749b17a4ef3bbb01'/>
<id>0d7bee10beeb59b1133bf5a4749b17a4ef3bbb01</id>
<content type='text'>
Pull x86 fixes from Ingo Molnar:

 - Fix AMD PCI root device caching regression that triggers
   on certain firmware variants

 - Fix the zen5_rdseed_microcode[] array to be NULL-terminated

 - Add more AMD models to microcode signature checking

* tag 'x86-urgent-2025-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode/AMD: Add more known models to entry sign checking
  x86/CPU/AMD: Add missing terminator for zen5_rdseed_microcode
  x86/amd_node: Fix AMD root device caching
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 fixes from Ingo Molnar:

 - Fix AMD PCI root device caching regression that triggers
   on certain firmware variants

 - Fix the zen5_rdseed_microcode[] array to be NULL-terminated

 - Add more AMD models to microcode signature checking

* tag 'x86-urgent-2025-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode/AMD: Add more known models to entry sign checking
  x86/CPU/AMD: Add missing terminator for zen5_rdseed_microcode
  x86/amd_node: Fix AMD root device caching
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: CPPC: Detect preferred core availability on online CPUs</title>
<updated>2025-11-07T17:37:42+00:00</updated>
<author>
<name>Gautham R. Shenoy</name>
<email>gautham.shenoy@amd.com</email>
</author>
<published>2025-11-07T07:41:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4fe5934db4a7187d358f1af1b3ef9b6dd59bce58'/>
<id>4fe5934db4a7187d358f1af1b3ef9b6dd59bce58</id>
<content type='text'>
Commit 279f838a61f9 ("x86/amd: Detect preferred cores in
amd_get_boost_ratio_numerator()") introduced the ability to detect the
preferred core on AMD platforms by checking if there at least two
distinct highest_perf values.

However, it uses for_each_present_cpu() to iterate through all the
CPUs in the platform, which is problematic when the kernel is booted
with "nosmt=force" commandline option.

Hence limit the search to only the online CPUs.

Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()")
Reported-by: Christopher Harris &lt;chris.harris79@gmail.com&gt;
Closes: https://lore.kernel.org/lkml/CAM+eXpdDT7KjLV0AxEwOLkSJ2QtrsvGvjA2cCHvt1d0k2_C4Cw@mail.gmail.com/
Reviewed-by: "Mario Limonciello (AMD) (kernel.org)" &lt;superm1@kernel.org&gt;
Tested-by: Chrisopher Harris &lt;chris.harris79@gmail.com&gt;
Signed-off-by: Gautham R. Shenoy &lt;gautham.shenoy@amd.com&gt;
Link: https://patch.msgid.link/20251107074145.2340-2-gautham.shenoy@amd.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 279f838a61f9 ("x86/amd: Detect preferred cores in
amd_get_boost_ratio_numerator()") introduced the ability to detect the
preferred core on AMD platforms by checking if there at least two
distinct highest_perf values.

However, it uses for_each_present_cpu() to iterate through all the
CPUs in the platform, which is problematic when the kernel is booted
with "nosmt=force" commandline option.

Hence limit the search to only the online CPUs.

Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()")
Reported-by: Christopher Harris &lt;chris.harris79@gmail.com&gt;
Closes: https://lore.kernel.org/lkml/CAM+eXpdDT7KjLV0AxEwOLkSJ2QtrsvGvjA2cCHvt1d0k2_C4Cw@mail.gmail.com/
Reviewed-by: "Mario Limonciello (AMD) (kernel.org)" &lt;superm1@kernel.org&gt;
Tested-by: Chrisopher Harris &lt;chris.harris79@gmail.com&gt;
Signed-off-by: Gautham R. Shenoy &lt;gautham.shenoy@amd.com&gt;
Link: https://patch.msgid.link/20251107074145.2340-2-gautham.shenoy@amd.com
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/microcode/AMD: Add more known models to entry sign checking</title>
<updated>2025-11-07T11:12:21+00:00</updated>
<author>
<name>Mario Limonciello (AMD)</name>
<email>superm1@kernel.org</email>
</author>
<published>2025-11-06T18:28:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d23550efc6800841b4d1639784afaebdea946ae0'/>
<id>d23550efc6800841b4d1639784afaebdea946ae0</id>
<content type='text'>
Two Zen5 systems are missing from need_sha_check(). Add them.

Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches")
Signed-off-by: Mario Limonciello (AMD) &lt;superm1@kernel.org&gt;
Signed-off-by: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: &lt;stable@kernel.org&gt;
Link: https://patch.msgid.link/20251106182904.4143757-1-superm1@kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Two Zen5 systems are missing from need_sha_check(). Add them.

Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches")
Signed-off-by: Mario Limonciello (AMD) &lt;superm1@kernel.org&gt;
Signed-off-by: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: &lt;stable@kernel.org&gt;
Link: https://patch.msgid.link/20251106182904.4143757-1-superm1@kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/fgraph,bpf: Fix stack ORC unwind from kprobe_multi return probe</title>
<updated>2025-11-06T01:05:19+00:00</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@kernel.org</email>
</author>
<published>2025-11-04T21:54:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=20a0bc10272fa17a44fc857c31574a8306f60d20'/>
<id>20a0bc10272fa17a44fc857c31574a8306f60d20</id>
<content type='text'>
Currently we don't get stack trace via ORC unwinder on top of fgraph exit
handler. We can see that when generating stacktrace from kretprobe_multi
bpf program which is based on fprobe/fgraph.

The reason is that the ORC unwind code won't get pass the return_to_handler
callback installed by fgraph return probe machinery.

Solving this by creating stack frame in return_to_handler expected by
ftrace_graph_ret_addr function to recover original return address and
continue with the unwind.

Also updating the pt_regs data with cs/flags/rsp which are needed for
successful stack retrieval from ebpf bpf_get_stackid helper.
 - in get_perf_callchain we check user_mode(regs) so CS has to be set
 - in perf_callchain_kernel we call perf_hw_regs(regs), so EFLAGS/FIXED
    has to be unset

Acked-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/r/20251104215405.168643-3-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently we don't get stack trace via ORC unwinder on top of fgraph exit
handler. We can see that when generating stacktrace from kretprobe_multi
bpf program which is based on fprobe/fgraph.

The reason is that the ORC unwind code won't get pass the return_to_handler
callback installed by fgraph return probe machinery.

Solving this by creating stack frame in return_to_handler expected by
ftrace_graph_ret_addr function to recover original return address and
continue with the unwind.

Also updating the pt_regs data with cs/flags/rsp which are needed for
successful stack retrieval from ebpf bpf_get_stackid helper.
 - in get_perf_callchain we check user_mode(regs) so CS has to be set
 - in perf_callchain_kernel we call perf_hw_regs(regs), so EFLAGS/FIXED
    has to be unset

Acked-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/r/20251104215405.168643-3-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: uaccess: don't use runtime-const rewriting in modules</title>
<updated>2025-11-05T01:24:36+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-11-04T06:25:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=284922f4c563aa3a8558a00f2a05722133237fe8'/>
<id>284922f4c563aa3a8558a00f2a05722133237fe8</id>
<content type='text'>
The runtime-const infrastructure was never designed to handle the
modular case, because the constant fixup is only done at boot time for
core kernel code.

But by the time I used it for the x86-64 user space limit handling in
commit 86e6b1547b3d ("x86: fix user address masking non-canonical
speculation issue"), I had completely repressed that fact.

And it all happens to work because the only code that currently actually
gets inlined by modules is for the access_ok() limit check, where the
default constant value works even when not fixed up.  Because at least I
had intentionally made it be something that is in the non-canonical
address space region.

But it's technically very wrong, and it does mean that at least in
theory, the use of 'access_ok()' + '__get_user()' can trigger the same
speculation issue with non-canonical addresses that the original commit
was all about.

The pattern is unusual enough that this probably doesn't matter in
practice, but very wrong is still very wrong.  Also, let's fix it before
the nice optimized scoped user accessor helpers that Thomas Gleixner is
working on cause this pseudo-constant to then be more widely used.

This all came up due to an unrelated discussion with Mateusz Guzik about
using the runtime const infrastructure for names_cachep accesses too.
There the modular case was much more obviously broken, and Mateusz noted
it in his 'v2' of the patch series.

That then made me notice how broken 'access_ok()' had been in modules
all along.  Mea culpa, mea maxima culpa.

Fix it by simply not using the runtime-const code in modules, and just
using the USER_PTR_MAX variable value instead.  This is not
performance-critical like the core user accessor functions (get_user()
and friends) are.

Also make sure this doesn't get forgotten the next time somebody wants
to do runtime constant optimizations by having the x86 runtime-const.h
header file error out if included by modules.

Fixes: 86e6b1547b3d ("x86: fix user address masking non-canonical speculation issue")
Acked-by: Borislav Petkov &lt;bp@alien8.de&gt;
Acked-by: Sean Christopherson &lt;seanjc@google.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Triggered-by: Mateusz Guzik &lt;mjguzik@gmail.com&gt;
Link: https://lore.kernel.org/all/20251030105242.801528-1-mjguzik@gmail.com/
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
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<pre>
The runtime-const infrastructure was never designed to handle the
modular case, because the constant fixup is only done at boot time for
core kernel code.

But by the time I used it for the x86-64 user space limit handling in
commit 86e6b1547b3d ("x86: fix user address masking non-canonical
speculation issue"), I had completely repressed that fact.

And it all happens to work because the only code that currently actually
gets inlined by modules is for the access_ok() limit check, where the
default constant value works even when not fixed up.  Because at least I
had intentionally made it be something that is in the non-canonical
address space region.

But it's technically very wrong, and it does mean that at least in
theory, the use of 'access_ok()' + '__get_user()' can trigger the same
speculation issue with non-canonical addresses that the original commit
was all about.

The pattern is unusual enough that this probably doesn't matter in
practice, but very wrong is still very wrong.  Also, let's fix it before
the nice optimized scoped user accessor helpers that Thomas Gleixner is
working on cause this pseudo-constant to then be more widely used.

This all came up due to an unrelated discussion with Mateusz Guzik about
using the runtime const infrastructure for names_cachep accesses too.
There the modular case was much more obviously broken, and Mateusz noted
it in his 'v2' of the patch series.

That then made me notice how broken 'access_ok()' had been in modules
all along.  Mea culpa, mea maxima culpa.

Fix it by simply not using the runtime-const code in modules, and just
using the USER_PTR_MAX variable value instead.  This is not
performance-critical like the core user accessor functions (get_user()
and friends) are.

Also make sure this doesn't get forgotten the next time somebody wants
to do runtime constant optimizations by having the x86 runtime-const.h
header file error out if included by modules.

Fixes: 86e6b1547b3d ("x86: fix user address masking non-canonical speculation issue")
Acked-by: Borislav Petkov &lt;bp@alien8.de&gt;
Acked-by: Sean Christopherson &lt;seanjc@google.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Triggered-by: Mateusz Guzik &lt;mjguzik@gmail.com&gt;
Link: https://lore.kernel.org/all/20251030105242.801528-1-mjguzik@gmail.com/
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
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