| Message ID | 1407448539-25870-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index 57a8ff9..36a8bdd 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-3.13.y-queue branch of the 3.13.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-3.13.y-queue This patch is scheduled to be released in version 3.13.11.6. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From f284f10e4c5be7affd1467f5427a0afd913e3225 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> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- arch/powerpc/perf/core-book3s.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) -- 1.9.1