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

From: Michael Ellerman
Date: Thu Feb 27 2020 - 07:31:38 EST


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 <mpe@xxxxxxxxxxxxxx>
> Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx>

Applied to powerpc fixes, thanks.

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

cheers