| Message ID | 1407333235-16434-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index c05f10e95a9e..d5d7adf6dc50 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -1159,14 +1159,14 @@ static void power_pmu_enable(struct pmu *pmu) cpuhw->mmcr[0] |= MMCR0_PMXE | MMCR0_FCECE; out_enable: + if (ppmu->flags & PPMU_ARCH_207S) + mtspr(SPRN_MMCR2, 0); + mmcr0 = ebb_switch_in(ebb, cpuhw->mmcr[0]); mb(); write_mmcr0(cpuhw, mmcr0); - if (ppmu->flags & PPMU_ARCH_207S) - mtspr(SPRN_MMCR2, 0); - /* * Enable instruction sampling if necessary */
This is a note to let you know that I have just added a patch titled powerpc/perf: Fix MMCR2 handling for EBB to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.11.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 56334a950e99419e966a707e8adf92fce12cefad Mon Sep 17 00:00:00 2001 From: Michael Ellerman <mpe@ellerman.id.au> Date: Wed, 23 Jul 2014 17:20:04 +1000 Subject: powerpc/perf: Fix MMCR2 handling for EBB commit 8903461c9bc56fcb041fb92d054e2529951770b6 upstream. In the recent commit b50a6c584bb4 "Clear MMCR2 when enabling PMU", I screwed up the handling of MMCR2 for tasks using EBB. We must make sure we set MMCR2 *before* ebb_switch_in(), otherwise we overwrite the value of MMCR2 that userspace may have written. That potentially breaks a task that uses EBB and manually uses MMCR2 for event freezing. Fixes: b50a6c584bb4 ("powerpc/perf: Clear MMCR2 when enabling PMU") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [ luis: backported to 3.11: adjusted context ] Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- arch/powerpc/perf/core-book3s.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) -- 1.9.1