diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-10-21 15:30:09 -1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-10-21 15:30:09 -1000 |
| commit | 0a3221b65874b5089f1742de59ef89f032b9f2ea (patch) | |
| tree | cccf2064257e8184fd2225c25019a486b7b6bb58 /arch | |
| parent | 2f111a6fd5b5297b4e92f53798ca086f7c7d33a4 (diff) | |
| parent | 787252a10d9422f3058df9a4821f389e5326c440 (diff) | |
Merge tag 'powerpc-5.15-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
- Fix a bug exposed by a previous fix, where running guests with
certain SMT topologies could crash the host on Power8.
- Fix atomic sleep warnings when re-onlining CPUs, when PREEMPT is
enabled.
Thanks to Nathan Lynch, Srikar Dronamraju, and Valentin Schneider.
* tag 'powerpc-5.15-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/smp: do not decrement idle task preempt count in CPU offline
powerpc/idle: Don't corrupt back chain when going idle
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/idle_book3s.S | 10 | ||||
| -rw-r--r-- | arch/powerpc/kernel/smp.c | 2 |
2 files changed, 6 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S index abb719b21cae..3d97fb833834 100644 --- a/arch/powerpc/kernel/idle_book3s.S +++ b/arch/powerpc/kernel/idle_book3s.S @@ -126,14 +126,16 @@ _GLOBAL(idle_return_gpr_loss) /* * This is the sequence required to execute idle instructions, as * specified in ISA v2.07 (and earlier). MSR[IR] and MSR[DR] must be 0. - * - * The 0(r1) slot is used to save r2 in isa206, so use that here. + * We have to store a GPR somewhere, ptesync, then reload it, and create + * a false dependency on the result of the load. It doesn't matter which + * GPR we store, or where we store it. We have already stored r2 to the + * stack at -8(r1) in isa206_idle_insn_mayloss, so use that. */ #define IDLE_STATE_ENTER_SEQ_NORET(IDLE_INST) \ /* Magic NAP/SLEEP/WINKLE mode enter sequence */ \ - std r2,0(r1); \ + std r2,-8(r1); \ ptesync; \ - ld r2,0(r1); \ + ld r2,-8(r1); \ 236: cmpd cr0,r2,r2; \ bne 236b; \ IDLE_INST; \ diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 9cc7d3dbf439..605bab448f84 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -1730,8 +1730,6 @@ void __cpu_die(unsigned int cpu) void arch_cpu_idle_dead(void) { - sched_preempt_enable_no_resched(); - /* * Disable on the down path. This will be re-enabled by * start_secondary() via start_secondary_resume() below |