| Message ID | 1479184113.2608.45.camel@kernel.crashing.org (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Tue, 2016-15-11 at 04:28:33 UTC, Benjamin Herrenschmidt wrote: > Commit d3cbff1b5 "powerpc: Put exception configuration in a common place" > broke the setting of the AIL bit (which enables taking exceptions with > the MMU still on) on all processors, moving it incorrectly to a function > called only on the boot CPU. This was correct for the guest case but > not when running in hypervisor mode. > > This fixes it by partially reverting that commit, putting the setting > back in cpu_ready_for_interrupts() > > Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> > Fixes: d3cbff1b5 ("powerpc: Put exception configuration in a common place") > CC: stable@vger.kernel.org # v4.8+ Applied to powerpc fixes, thanks. https://git.kernel.org/powerpc/c/c0a36013639b06760f7c2c21a8387e cheers
On Tue, 2016-11-15 at 15:28 +1100, Benjamin Herrenschmidt wrote: > Commit d3cbff1b5 "powerpc: Put exception configuration in a common place" > broke the setting of the AIL bit (which enables taking exceptions with > the MMU still on) on all processors, moving it incorrectly to a function > called only on the boot CPU. This was correct for the guest case but > not when running in hypervisor mode. > > This fixes it by partially reverting that commit, putting the setting > back in cpu_ready_for_interrupts() > > Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> > Fixes: d3cbff1b5 ("powerpc: Put exception configuration in a common place") > CC: stable@vger.kernel.org # v4.8+ Acked-By: Michael Neuling <mikey@neuling.org> > --- > arch/powerpc/kernel/setup_64.c | 20 ++++++++++++++------ > 1 file changed, 14 insertions(+), 6 deletions(-) > > diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c > index 7ac8e6e..ac75224 100644 > --- a/arch/powerpc/kernel/setup_64.c > +++ b/arch/powerpc/kernel/setup_64.c > @@ -226,17 +226,25 @@ static void __init configure_exceptions(void) > if (firmware_has_feature(FW_FEATURE_OPAL)) > opal_configure_cores(); > > - /* Enable AIL if supported, and we are in hypervisor mode */ > - if (early_cpu_has_feature(CPU_FTR_HVMODE) && > - early_cpu_has_feature(CPU_FTR_ARCH_207S)) { > - unsigned long lpcr = mfspr(SPRN_LPCR); > - mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3); > - } > + /* AIL on native is done in cpu_ready_for_interrupts */ > } > } > > static void cpu_ready_for_interrupts(void) > { > + /* > + * Enable AIL if supported, and we are in hypervisor mode. This > + * is called once for every processor. > + * > + * If we are not in hypervisor mode the job is done once for > + * the whole partition in configure_exceptions(). > + */ > + if (early_cpu_has_feature(CPU_FTR_HVMODE) && > + early_cpu_has_feature(CPU_FTR_ARCH_207S)) { > + unsigned long lpcr = mfspr(SPRN_LPCR); > + mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3); > + } > + > /* Set IR and DR in PACA MSR */ > get_paca()->kernel_msr = MSR_KERNEL; > } >
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 7ac8e6e..ac75224 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -226,17 +226,25 @@ static void __init configure_exceptions(void) if (firmware_has_feature(FW_FEATURE_OPAL)) opal_configure_cores(); - /* Enable AIL if supported, and we are in hypervisor mode */ - if (early_cpu_has_feature(CPU_FTR_HVMODE) && - early_cpu_has_feature(CPU_FTR_ARCH_207S)) { - unsigned long lpcr = mfspr(SPRN_LPCR); - mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3); - } + /* AIL on native is done in cpu_ready_for_interrupts */ } } static void cpu_ready_for_interrupts(void) { + /* + * Enable AIL if supported, and we are in hypervisor mode. This + * is called once for every processor. + * + * If we are not in hypervisor mode the job is done once for + * the whole partition in configure_exceptions(). + */ + if (early_cpu_has_feature(CPU_FTR_HVMODE) && + early_cpu_has_feature(CPU_FTR_ARCH_207S)) { + unsigned long lpcr = mfspr(SPRN_LPCR); + mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3); + } + /* Set IR and DR in PACA MSR */ get_paca()->kernel_msr = MSR_KERNEL; }
Commit d3cbff1b5 "powerpc: Put exception configuration in a common place" broke the setting of the AIL bit (which enables taking exceptions with the MMU still on) on all processors, moving it incorrectly to a function called only on the boot CPU. This was correct for the guest case but not when running in hypervisor mode. This fixes it by partially reverting that commit, putting the setting back in cpu_ready_for_interrupts() Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Fixes: d3cbff1b5 ("powerpc: Put exception configuration in a common place") CC: stable@vger.kernel.org # v4.8+ --- arch/powerpc/kernel/setup_64.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-)