Subject: Re: [PATCH] powerpc/watchpoint: Don't call dar_within_range() for Book3S

From: Michael Ellerman <[email-masked]>
Date: Thu, 27 Feb 2020 23:31:34 +1100 (AEDT)

On Sat, 2020-02-22 at 08:20:49 UTC, Ravi Bangoria wrote:
> DAR is set to the first byte of overlap between actual access and
> watched range at DSI on Book3S processor. But actual access range
> might or might not be within user asked range. So for Book3S, it
> must not call dar_within_range().
> 
> This revert portion of commit 39413ae00967 ("powerpc/hw_breakpoints:
> Rewrite 8xx breakpoints to allow any address range size.").
> 
> Before patch:
>   # ./tools/testing/selftests/powerpc/ptrace/perf-hwbreak
>   ...
>   TESTED: No overlap
>   FAILED: Partial overlap: 0 != 2
>   TESTED: Partial overlap
>   TESTED: No overlap
>   FAILED: Full overlap: 0 != 2
>   failure: perf_hwbreak
> 
> After patch:
>   TESTED: No overlap
>   TESTED: Partial overlap
>   TESTED: Partial overlap
>   TESTED: No overlap
>   TESTED: Full overlap
>   success: perf_hwbreak
> 
> Fixes: 39413ae00967 ("powerpc/hw_breakpoints: Rewrite 8xx breakpoints to allow any address range size.")
> Reported-by: Michael Ellerman <[email-masked]>
> Signed-off-by: Ravi Bangoria <[email-masked]>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/e08658a657f974590809290c62e889f0fd420200

cheers