diff mbox

powerpc/hw_brk: Fix off by one error when validating DAWR region end

Message ID 14367.1372652390@ale.ozlabs.ibm.com (mailing list archive)
State Accepted, archived
Commit e2a800beaca1f580945773e57d1a0e7cd37b1056
Headers show

Commit Message

Michael Neuling July 1, 2013, 4:19 a.m. UTC 
The Data Address Watchpoint Register (DAWR) on POWER8 can take a 512
byte range but this range must not cross a 512 byte boundary.

Unfortunately we were off by one when calculating the end of the region,
hence we were not allowing some breakpoint regions which were actually
valid.  This fixes this error.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Reported-by: Edjunior Barbosa Machado <emachado@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # 3.9+
diff mbox

Patch

diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c
index 1150ae7..f0b47d1 100644
--- a/arch/powerpc/kernel/hw_breakpoint.c
+++ b/arch/powerpc/kernel/hw_breakpoint.c
@@ -176,7 +176,7 @@  int arch_validate_hwbkpt_settings(struct perf_event *bp)
 		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) >> 10))
+		    ((bp->attr.bp_addr + bp->attr.bp_len - 1) >> 10))
 			return -EINVAL;
 	}
 	if (info->len >