On Mon, Aug 05, 2019 at 07:32:26AM +0200, gregkh@linuxfoundation.org wrote:

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

Backport for 4.4, 4.9 and 4.14 below.

Will

--->8

From 4cf2e5aed205d7a3958e67b9fa1e76be64543b1b Mon Sep 17 00:00:00 2001

From: Will Deacon will@kernel.org Date: Mon, 29 Jul 2019 11:06:17 +0100 Subject: [PATCH] arm64: compat: Allow single-byte watchpoints on all addresses

commit 849adec41203ac5837c40c2d7e08490ffdef3c2c upstream.

Commit d968d2b801d8 ("ARM: 7497/1: hw_breakpoint: allow single-byte watchpoints on all addresses") changed the validation requirements for hardware watchpoints on arch/arm/. Update our compat layer to implement the same relaxation.

Cc: stable@vger.kernel.org # 4.4.y, 4.9.y, 4.14.y Signed-off-by: Will Deacon will@kernel.org --- arch/arm64/kernel/hw_breakpoint.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c index eeebfc315526..036fbb959821 100644 --- a/arch/arm64/kernel/hw_breakpoint.c +++ b/arch/arm64/kernel/hw_breakpoint.c @@ -504,13 +504,14 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp) /* Aligned */ break; case 1: - /* Allow single byte watchpoint. */ - if (info->ctrl.len == ARM_BREAKPOINT_LEN_1) - break; case 2: /* Allow halfword watchpoints and breakpoints. */ if (info->ctrl.len == ARM_BREAKPOINT_LEN_2) break; + case 3: + /* Allow single byte watchpoint. */ + if (info->ctrl.len == ARM_BREAKPOINT_LEN_1) + break; default: return -EINVAL; }