| Message ID | 20180517053715.24011-1-mikey@neuling.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | cd6ef7eebf171bfcba7dc2df719c2a4958775040 |
| Headers | show |
| Series | [1/2] powerpc/ptrace: Fix enforcement of DAWR contraints | expand |
On Thu, 2018-05-17 at 05:37:14 UTC, Michael Neuling wrote: > Back when we first introduced the DAWR in this commit: > 4ae7ebe952 powerpc: Change hardware breakpoint to allow longer ranges > > We screwed up the constraint making it a 1024 byte boundary rather > than a 512. This makes the check overly permissive. Fortunately GDB is > the only real user and it always did they right thing, so we never > noticed. > > This fixes the constraint to 512 bytes. > > Signed-off-by: Michael Neuling <mikey@neuling.org> > cc: <stable@vger.kernel.org> # v3.9+ Series applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/cd6ef7eebf171bfcba7dc2df719c2a cheers
diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c index 4c1012b80d..80547dad37 100644 --- a/arch/powerpc/kernel/hw_breakpoint.c +++ b/arch/powerpc/kernel/hw_breakpoint.c @@ -178,8 +178,8 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp) if (cpu_has_feature(CPU_FTR_DAWR)) { length_max = 512 ; /* 64 doublewords */ /* DAWR region can't cross 512 boundary */ - if ((bp->attr.bp_addr >> 10) != - ((bp->attr.bp_addr + bp->attr.bp_len - 1) >> 10)) + if ((bp->attr.bp_addr >> 9) != + ((bp->attr.bp_addr + bp->attr.bp_len - 1) >> 9)) return -EINVAL; } if (info->len >
Back when we first introduced the DAWR in this commit: 4ae7ebe952 powerpc: Change hardware breakpoint to allow longer ranges We screwed up the constraint making it a 1024 byte boundary rather than a 512. This makes the check overly permissive. Fortunately GDB is the only real user and it always did they right thing, so we never noticed. This fixes the constraint to 512 bytes. Signed-off-by: Michael Neuling <mikey@neuling.org> cc: <stable@vger.kernel.org> # v3.9+ --- arch/powerpc/kernel/hw_breakpoint.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)