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authorDaniel Vetter <daniel.vetter@ffwll.ch>2012-09-24 18:07:48 +0200
committerDaniel Vetter <daniel.vetter@ffwll.ch>2012-09-24 18:17:12 +0200
commit398b7a1b882a655ee84bd985f6c2ba89082404ae (patch)
tree5eb9284a87ee2a45a10809cfbe3a66fea6ea53ae /arch/arm/kernel/hw_breakpoint.c
parent57df2ae9df6e335a98969cac5aafb09c4de10bb2 (diff)
parent979570e02981d4a8fc20b3cc8fd651856c98ee9d (diff)
Merge tag 'v3.6-rc7' into drm-intel-next-queued
Manual backmerge of -rc7 to resolve a silent conflict leading to compile failure in drivers/gpu/drm/i915/intel_hdmi.c. This is due to the bugfix in -rc7: commit b98b60167279df3acac9422c3c9820d9ebbcf9fb Author: Wang Xingchao <xingchao.wang@intel.com> Date: Thu Sep 13 07:43:22 2012 +0800 drm/i915: HDMI - Clear Audio Enable bit for Hot Plug Since this code moved around a lot in -next git put that snippet at the wrong spot. I've tried to fix this by making the conflict explicit by merging a version for next with: commit 3cce574f0190dd149472059fb69267cf83d290f9 Author: Wang Xingchao <xingchao.wang@intel.com> Date: Thu Sep 13 11:19:00 2012 +0800 drm/i915: HDMI - Clear Audio Enable bit for Hot Plug unconditionally But that failed to solve the entire problem. To avoid pushing out further -nightly branch to our QA where this is broken, do the backmerge and manually add the stuff git adds to -next from the patch in -fixes. Note that this doesn't show up in git's merge diff (and hence is also not handled by git rerere), which adds to the reasons why I'd like to fix this with a verbose backmerge. The git merge diff only shows a bunch of trivial conflicts of the "code changed in lines next to each another" kind. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'arch/arm/kernel/hw_breakpoint.c')
-rw-r--r--arch/arm/kernel/hw_breakpoint.c62
1 files changed, 44 insertions, 18 deletions
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index ba386bd9410..281bf330124 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -159,6 +159,12 @@ static int debug_arch_supported(void)
arch >= ARM_DEBUG_ARCH_V7_1;
}
+/* Can we determine the watchpoint access type from the fsr? */
+static int debug_exception_updates_fsr(void)
+{
+ return 0;
+}
+
/* Determine number of WRP registers available. */
static int get_num_wrp_resources(void)
{
@@ -604,13 +610,14 @@ 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:
ret = -EINVAL;
goto out;
@@ -619,18 +626,35 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
info->address &= ~alignment_mask;
info->ctrl.len <<= offset;
- /*
- * Currently we rely on an overflow handler to take
- * care of single-stepping the breakpoint when it fires.
- * In the case of userspace breakpoints on a core with V7 debug,
- * we can use the mismatch feature as a poor-man's hardware
- * single-step, but this only works for per-task breakpoints.
- */
- if (!bp->overflow_handler && (arch_check_bp_in_kernelspace(bp) ||
- !core_has_mismatch_brps() || !bp->hw.bp_target)) {
- pr_warning("overflow handler required but none found\n");
- ret = -EINVAL;
+ if (!bp->overflow_handler) {
+ /*
+ * Mismatch breakpoints are required for single-stepping
+ * breakpoints.
+ */
+ if (!core_has_mismatch_brps())
+ return -EINVAL;
+
+ /* We don't allow mismatch breakpoints in kernel space. */
+ if (arch_check_bp_in_kernelspace(bp))
+ return -EPERM;
+
+ /*
+ * Per-cpu breakpoints are not supported by our stepping
+ * mechanism.
+ */
+ if (!bp->hw.bp_target)
+ return -EINVAL;
+
+ /*
+ * We only support specific access types if the fsr
+ * reports them.
+ */
+ if (!debug_exception_updates_fsr() &&
+ (info->ctrl.type == ARM_BREAKPOINT_LOAD ||
+ info->ctrl.type == ARM_BREAKPOINT_STORE))
+ return -EINVAL;
}
+
out:
return ret;
}
@@ -706,10 +730,12 @@ static void watchpoint_handler(unsigned long addr, unsigned int fsr,
goto unlock;
/* Check that the access type matches. */
- access = (fsr & ARM_FSR_ACCESS_MASK) ? HW_BREAKPOINT_W :
- HW_BREAKPOINT_R;
- if (!(access & hw_breakpoint_type(wp)))
- goto unlock;
+ if (debug_exception_updates_fsr()) {
+ access = (fsr & ARM_FSR_ACCESS_MASK) ?
+ HW_BREAKPOINT_W : HW_BREAKPOINT_R;
+ if (!(access & hw_breakpoint_type(wp)))
+ goto unlock;
+ }
/* We have a winner. */
info->trigger = addr;