On 02/22/2020 08:20 AM, 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.")
Oh, this seems to have been introduced by 27985b2a640e
("powerpc/watchpoint: Don't ignore extraneous exceptions blindly").
I must have lost it through a rebase as we were doing our series
approximately at the same time, sorry for that.
Reviewed-by: Christophe Leroy <christophe.le...@c-s.fr>
Reported-by: Michael Ellerman <m...@ellerman.id.au>
Signed-off-by: Ravi Bangoria <ravi.bango...@linux.ibm.com>
---
arch/powerpc/kernel/hw_breakpoint.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/kernel/hw_breakpoint.c
b/arch/powerpc/kernel/hw_breakpoint.c
index 2462cd7c565c..d0854320bb50 100644
--- a/arch/powerpc/kernel/hw_breakpoint.c
+++ b/arch/powerpc/kernel/hw_breakpoint.c
@@ -331,11 +331,13 @@ int hw_breakpoint_handler(struct die_args *args)
}
info->type &= ~HW_BRK_TYPE_EXTRANEOUS_IRQ;
- if (!dar_within_range(regs->dar, info))
- info->type |= HW_BRK_TYPE_EXTRANEOUS_IRQ;
-
- if (!IS_ENABLED(CONFIG_PPC_8xx) && !stepping_handler(regs, bp, info))
- goto out;
+ if (IS_ENABLED(CONFIG_PPC_8xx)) {
+ if (!dar_within_range(regs->dar, info))
+ info->type |= HW_BRK_TYPE_EXTRANEOUS_IRQ;
+ } else {
+ if (!stepping_handler(regs, bp, info))
+ goto out;
+ }
/*
* As a policy, the callback is invoked in a 'trigger-after-execute'