[PATCH] alpha: add simd_enabled argument to perf_reg_validate()

[PATCH] alpha: add simd_enabled argument to perf_reg_validate()

[Thomas Weißschuh]

Align the alpha function with the generic function signature.
The alpha function was added in commit 9280e99d87dd ("alpha: add
HAVE_PERF_REGS and HAVE_PERF_USER_STACK_DUMP support") while the
generic function signature was changed in commit a2c64c74c029 ("perf:
Enhance perf_reg_validate() with simd_enabled argument").

After both commits landed in Linus' tree the signatures now differ,
resulting in a build error:

arch/alpha/kernel/perf_regs.c:46:5: error: conflicting types for 'perf_reg_validate'; have 'int(u64)' {aka 'int(long long unsigned int)'}
   46 | int perf_reg_validate(u64 mask)
      |     ^~~~~~~~~~~~~~~~~
In file included from include/linux/perf_event.h:50,
                 from arch/alpha/kernel/perf_regs.c:4:
include/linux/perf_regs.h:13:5: note: previous declaration of 'perf_reg_validate' with type 'int(u64,  bool)' {aka 'int(long long unsigned int,  _Bool)'}
   13 | int perf_reg_validate(u64 mask, bool simd_enabled);
      |     ^~~~~~~~~~~~~~~~~

Add the missing argument.

Fixes: 742f62b63904 ("Merge tag 'alpha-for-v7.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 arch/alpha/kernel/perf_regs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/alpha/kernel/perf_regs.c b/arch/alpha/kernel/perf_regs.c
index 33ea2e831ba0..c5a55bfa15a5 100644
--- a/arch/alpha/kernel/perf_regs.c
+++ b/arch/alpha/kernel/perf_regs.c
@@ -43,7 +43,7 @@ u64 perf_reg_value(struct pt_regs *regs, int idx)
 	return *(unsigned long *)((void *)regs + pt_regs_offset[idx]);
 }
 
-int perf_reg_validate(u64 mask)
+int perf_reg_validate(u64 mask, bool simd_enabled)
 {
 	if (!mask || mask & REG_RESERVED)
 		return -EINVAL;

---
base-commit: 2c455ddca7827ad8fa3a64fdbf5a60efb928b46a
change-id: 20261021-alpha-perf_reg_validate-c9b0a144fd3c

Best regards,
--  
Thomas Weißschuh <thomas.weissschuh@linutronix.de>

Re: [PATCH] alpha: add simd_enabled argument to perf_reg_validate()

[Magnus Lindholm]

Hi Thomas,

On Wed, Oct 21, 2026 at 10:18 AM Thomas Weißschuh
<thomas.weissschuh@linutronix.de> wrote:
>
> Align the alpha function with the generic function signature.
> The alpha function was added in commit 9280e99d87dd ("alpha: add
> HAVE_PERF_REGS and HAVE_PERF_USER_STACK_DUMP support") while the
> generic function signature was changed in commit a2c64c74c029 ("perf:
> Enhance perf_reg_validate() with simd_enabled argument").
>
> After both commits landed in Linus' tree the signatures now differ,
> resulting in a build error:
>
> arch/alpha/kernel/perf_regs.c:46:5: error: conflicting types for 'perf_reg_validate'; have 'int(u64)' {aka 'int(long long unsigned int)'}
>    46 | int perf_reg_validate(u64 mask)
>       |     ^~~~~~~~~~~~~~~~~
> In file included from include/linux/perf_event.h:50,
>                  from arch/alpha/kernel/perf_regs.c:4:
> include/linux/perf_regs.h:13:5: note: previous declaration of 'perf_reg_validate' with type 'int(u64,  bool)' {aka 'int(long long unsigned int,  _Bool)'}
>    13 | int perf_reg_validate(u64 mask, bool simd_enabled);
>       |     ^~~~~~~~~~~~~~~~~
>
> Add the missing argument.
>
> Fixes: 742f62b63904 ("Merge tag 'alpha-for-v7.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha")
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
>  arch/alpha/kernel/perf_regs.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/alpha/kernel/perf_regs.c b/arch/alpha/kernel/perf_regs.c
> index 33ea2e831ba0..c5a55bfa15a5 100644
> --- a/arch/alpha/kernel/perf_regs.c
> +++ b/arch/alpha/kernel/perf_regs.c
> @@ -43,7 +43,7 @@ u64 perf_reg_value(struct pt_regs *regs, int idx)
>         return *(unsigned long *)((void *)regs + pt_regs_offset[idx]);
>  }
>
> -int perf_reg_validate(u64 mask)
> +int perf_reg_validate(u64 mask, bool simd_enabled)
>  {
>         if (!mask || mask & REG_RESERVED)
>                 return -EINVAL;
>
> ---
> base-commit: 2c455ddca7827ad8fa3a64fdbf5a60efb928b46a
> change-id: 20261021-alpha-perf_reg_validate-c9b0a144fd3c
>
> Best regards,
> --
> Thomas Weißschuh <thomas.weissschuh@linutronix.de>
>

Thanks for catching this. I reproduced the build failure on current
mainline and confirmed your fix with GENERIC SMP and DP264 UP builds.
Both also passed perf register validation and sampling tests in QEMU.

Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Magnus Lindholm <linmag7@gmail.com>

If you have a route for this patch upstream, please go ahead and take it,
unless Linus would prefer to pick it up directly.


Thanks,
Magnus

Re: [PATCH] alpha: add simd_enabled argument to perf_reg_validate()

[Thomas Weißschuh]

Hi Magnus!

On Wed, Oct 21, 2026 at 12:23:55PM +0200, Magnus Lindholm wrote:
> On Wed, Oct 21, 2026 at 10:18 AM Thomas Weißschuh
> <thomas.weissschuh@linutronix.de> wrote:

(...)

> Thanks for catching this. I reproduced the build failure on current
> mainline and confirmed your fix with GENERIC SMP and DP264 UP builds.
> Both also passed perf register validation and sampling tests in QEMU.
> 
> Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
> Tested-by: Magnus Lindholm <linmag7@gmail.com>

Thanks.

> If you have a route for this patch upstream, please go ahead and take it,
> unless Linus would prefer to pick it up directly.

I have no route upstream. I hope for Linus to pick it up.
But if that does not happen, maybe you could send a PR.

How this issue made it past -next would also be interesting to know.


Thomas

Re: [PATCH] alpha: add simd_enabled argument to perf_reg_validate()

[Peter Zijlstra]

On Wed, Oct 21, 2026 at 01:49:35PM +0200, Thomas Weißschuh wrote:
> Hi Magnus!
> 
> On Wed, Oct 21, 2026 at 12:23:55PM +0200, Magnus Lindholm wrote:
> > On Wed, Oct 21, 2026 at 10:18 AM Thomas Weißschuh
> > <thomas.weissschuh@linutronix.de> wrote:
> 
> (...)
> 
> > Thanks for catching this. I reproduced the build failure on current
> > mainline and confirmed your fix with GENERIC SMP and DP264 UP builds.
> > Both also passed perf register validation and sampling tests in QEMU.
> > 
> > Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
> > Tested-by: Magnus Lindholm <linmag7@gmail.com>
> 
> Thanks.
> 
> > If you have a route for this patch upstream, please go ahead and take it,
> > unless Linus would prefer to pick it up directly.
> 
> I have no route upstream. I hope for Linus to pick it up.
> But if that does not happen, maybe you could send a PR.

I can stick it in tip/perf/urgent if that helps :-) I'm the one merging
the broken patch in the first place I suppose :/

> How this issue made it past -next would also be interesting to know.

Yeah this; normally I get robots screaming at me for things like this.

Re: [PATCH] alpha: add simd_enabled argument to perf_reg_validate()

[Peter Zijlstra]

On Wed, Oct 21, 2026 at 05:38:56PM +0200, Peter Zijlstra wrote:
> On Wed, Oct 21, 2026 at 01:49:35PM +0200, Thomas Weißschuh wrote:
> > Hi Magnus!
> > 
> > On Wed, Oct 21, 2026 at 12:23:55PM +0200, Magnus Lindholm wrote:
> > > On Wed, Oct 21, 2026 at 10:18 AM Thomas Weißschuh
> > > <thomas.weissschuh@linutronix.de> wrote:
> > 
> > (...)
> > 
> > > Thanks for catching this. I reproduced the build failure on current
> > > mainline and confirmed your fix with GENERIC SMP and DP264 UP builds.
> > > Both also passed perf register validation and sampling tests in QEMU.
> > > 
> > > Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
> > > Tested-by: Magnus Lindholm <linmag7@gmail.com>
> > 
> > Thanks.
> > 
> > > If you have a route for this patch upstream, please go ahead and take it,
> > > unless Linus would prefer to pick it up directly.
> > 
> > I have no route upstream. I hope for Linus to pick it up.
> > But if that does not happen, maybe you could send a PR.
> 
> I can stick it in tip/perf/urgent if that helps :-) 

It should be there; please yell if I should drop it because someone else
(alpha tree) wants it or something.

[tip: perf/urgent] alpha: add simd_enabled argument to perf_reg_validate()

[tip-bot2 for Thomas Weißschuh]

The following commit has been merged into the perf/urgent branch of tip:

Commit-ID:     2b774b5bbffabae7ac6be98a98e9641fb3c0bbb4
Gitweb:        https://git.kernel.org/tip/2b774b5bbffabae7ac6be98a98e9641fb3c0bbb4
Author:        Thomas Weißschuh <thomas.weissschuh@linutronix.de>
AuthorDate:    Wed, 21 Oct 2026 10:18:22 +02:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Wed, 21 Oct 2026 17:42:37 +02:00

alpha: add simd_enabled argument to perf_reg_validate()

Align the alpha function with the generic function signature.
The alpha function was added in commit 9280e99d87dd ("alpha: add
HAVE_PERF_REGS and HAVE_PERF_USER_STACK_DUMP support") while the
generic function signature was changed in commit a2c64c74c029 ("perf:
Enhance perf_reg_validate() with simd_enabled argument").

After both commits landed in Linus' tree the signatures now differ,
resulting in a build error:

arch/alpha/kernel/perf_regs.c:46:5: error: conflicting types for 'perf_reg_validate'; have 'int(u64)' {aka 'int(long long unsigned int)'}
   46 | int perf_reg_validate(u64 mask)
      |     ^~~~~~~~~~~~~~~~~
In file included from include/linux/perf_event.h:50,
                 from arch/alpha/kernel/perf_regs.c:4:
include/linux/perf_regs.h:13:5: note: previous declaration of 'perf_reg_validate' with type 'int(u64,  bool)' {aka 'int(long long unsigned int,  _Bool)'}
   13 | int perf_reg_validate(u64 mask, bool simd_enabled);
      |     ^~~~~~~~~~~~~~~~~

Add the missing argument.

Fixes: 742f62b63904 ("Merge tag 'alpha-for-v7.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/lindholm/alpha")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Link: https://patch.msgid.link/20261021-alpha-perf_reg_validate-v1-1-a8e8cc23ea7a@linutronix.de
---
 arch/alpha/kernel/perf_regs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/alpha/kernel/perf_regs.c b/arch/alpha/kernel/perf_regs.c
index 33ea2e8..c5a55bf 100644
--- a/arch/alpha/kernel/perf_regs.c
+++ b/arch/alpha/kernel/perf_regs.c
@@ -43,7 +43,7 @@ u64 perf_reg_value(struct pt_regs *regs, int idx)
 	return *(unsigned long *)((void *)regs + pt_regs_offset[idx]);
 }
 
-int perf_reg_validate(u64 mask)
+int perf_reg_validate(u64 mask, bool simd_enabled)
 {
 	if (!mask || mask & REG_RESERVED)
 		return -EINVAL;