From: Nicholas Piggin Date: Thu, 13 Oct 2022 15:16:45 +0000 (+1000) Subject: powerpc/64s: Disable preemption in hash lazy mmu mode X-Git-Tag: v6.6.17~6087^2~14 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b9ef323ea1682f9837bf63ba10c5e3750f71a20a;p=platform%2Fkernel%2Flinux-rpi.git powerpc/64s: Disable preemption in hash lazy mmu mode apply_to_page_range on kernel pages does not disable preemption, which is a requirement for hash's lazy mmu mode, which keeps track of the TLBs to flush with a per-cpu array. Reported-by: Guenter Roeck Signed-off-by: Nicholas Piggin Tested-by: Guenter Roeck Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20221013151647.1857994-1-npiggin@gmail.com --- diff --git a/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h b/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h index fab8332..751921f 100644 --- a/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h +++ b/arch/powerpc/include/asm/book3s/64/tlbflush-hash.h @@ -32,6 +32,11 @@ static inline void arch_enter_lazy_mmu_mode(void) if (radix_enabled()) return; + /* + * apply_to_page_range can call us this preempt enabled when + * operating on kernel page tables. + */ + preempt_disable(); batch = this_cpu_ptr(&ppc64_tlb_batch); batch->active = 1; } @@ -47,6 +52,7 @@ static inline void arch_leave_lazy_mmu_mode(void) if (batch->index) __flush_tlb_pending(batch); batch->active = 0; + preempt_enable(); } #define arch_flush_lazy_mmu_mode() do {} while (0)