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powerpc/watchpoint: Don't call dar_within_range() for Book3S

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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 39413ae009 ("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: 39413ae009 ("powerpc/hw_breakpoints: Rewrite 8xx breakpoints to allow any address range size.")
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200222082049.330435-1-ravi.bangoria@linux.ibm.com
This commit is contained in:
Ravi Bangoria 2020-02-22 13:50:49 +05:30 committed by Michael Ellerman
parent 9eb425b2e0
commit e08658a657
1 changed files with 7 additions and 5 deletions
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6
arch/powerpc/kernel/hw_breakpoint.c
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@ -331,11 +331,13 @@ int hw_breakpoint_handler(struct die_args *args)
} }
info->type &= ~HW_BRK_TYPE_EXTRANEOUS_IRQ; info->type &= ~HW_BRK_TYPE_EXTRANEOUS_IRQ;
if (IS_ENABLED(CONFIG_PPC_8xx)) {
if (!dar_within_range(regs->dar, info)) if (!dar_within_range(regs->dar, info))
info->type |= HW_BRK_TYPE_EXTRANEOUS_IRQ; info->type |= HW_BRK_TYPE_EXTRANEOUS_IRQ;
} else {
if (!IS_ENABLED(CONFIG_PPC_8xx) && !stepping_handler(regs, bp, info)) if (!stepping_handler(regs, bp, info))
goto out; goto out;
}
/* /*
* As a policy, the callback is invoked in a 'trigger-after-execute' * As a policy, the callback is invoked in a 'trigger-after-execute'