From e08658a657f974590809290c62e889f0fd420200 Mon Sep 17 00:00:00 2001 From: Ravi Bangoria Date: Sat, 22 Feb 2020 13:50:49 +0530 Subject: [PATCH] powerpc/watchpoint: Don't call dar_within_range() for Book3S 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 Signed-off-by: Ravi Bangoria Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200222082049.330435-1-ravi.bangoria@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 2462cd7..d085432 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' -- 2.7.4