[RFC PATCH v2 07/10] powerpc/book3s: Flush SLB/TLBs if we get SLB/TLB machine check errors on power8.
From: Mahesh J Salgaonkar <hidden>
Date: 2013-08-16 08:05:06
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
From: Mahesh Salgaonkar <redacted> This patch handles the memory errors on power8. If we get a machine check exception due to SLB or TLB errors, then flush SLBs/TLBs and reload SLBs to recover. I do not have access to power8 box, hence this patch haven't been tested yet. Signed-off-by: Mahesh Salgaonkar <redacted> --- arch/powerpc/include/asm/mce.h | 3 +++ arch/powerpc/kernel/cputable.c | 4 ++++ arch/powerpc/kernel/mce_power.c | 34 ++++++++++++++++++++++++++++++++++ 3 files changed, 41 insertions(+)
diff --git a/arch/powerpc/include/asm/mce.h b/arch/powerpc/include/asm/mce.h
index ba19073..6866062 100644
--- a/arch/powerpc/include/asm/mce.h
+++ b/arch/powerpc/include/asm/mce.h@@ -64,4 +64,7 @@ P7_DSISR_MC_SLB_MULTIHIT | \ P7_DSISR_MC_SLB_MULTIHIT_PARITY) +#define P8_DSISR_MC_SLB_ERRORS (P7_DSISR_MC_SLB_ERRORS | \ + P8_DSISR_MC_ERAT_MULTIHIT_SEC) + #endif /* __ASM_PPC64_MCE_H__ */
diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c
index c28cc2c..0195358 100644
--- a/arch/powerpc/kernel/cputable.c
+++ b/arch/powerpc/kernel/cputable.c@@ -74,6 +74,7 @@ extern void __restore_cpu_a2(void); extern void __flush_tlb_power7(unsigned long inval_selector); extern void __flush_tlb_power8(unsigned long inval_selector); extern long __machine_check_early_realmode_p7(struct pt_regs *regs); +extern long __machine_check_early_realmode_p8(struct pt_regs *regs); #endif /* CONFIG_PPC64 */ #if defined(CONFIG_E500) extern void __setup_cpu_e5500(unsigned long offset, struct cpu_spec* spec);
@@ -462,6 +463,7 @@ static struct cpu_spec __initdata cpu_specs[] = { .cpu_setup = __setup_cpu_power8, .cpu_restore = __restore_cpu_power8, .flush_tlb = __flush_tlb_power8, + .machine_check_early = __machine_check_early_realmode_p8, .platform = "power8", }, { /* Power7 */
@@ -521,6 +523,7 @@ static struct cpu_spec __initdata cpu_specs[] = { .cpu_setup = __setup_cpu_power8, .cpu_restore = __restore_cpu_power8, .flush_tlb = __flush_tlb_power8, + .machine_check_early = __machine_check_early_realmode_p8, .platform = "power8", }, { /* Power8 */
@@ -540,6 +543,7 @@ static struct cpu_spec __initdata cpu_specs[] = { .cpu_setup = __setup_cpu_power8, .cpu_restore = __restore_cpu_power8, .flush_tlb = __flush_tlb_power8, + .machine_check_early = __machine_check_early_realmode_p8, .platform = "power8", }, { /* Cell Broadband Engine */
diff --git a/arch/powerpc/kernel/mce_power.c b/arch/powerpc/kernel/mce_power.c
index 645d722..949d102 100644
--- a/arch/powerpc/kernel/mce_power.c
+++ b/arch/powerpc/kernel/mce_power.c@@ -151,3 +151,37 @@ long __machine_check_early_realmode_p7(struct pt_regs *regs) /* TODO: Decode machine check reason. */ return handled; } + +static long mce_handle_ierror_p8(uint64_t srr1) +{ + long handled = 0; + + handled = mce_handle_common_ierror(srr1); + + if (P7_SRR1_MC_IFETCH(srr1) == P8_SRR1_MC_IFETCH_ERAT_MULTIHIT) { + flush_and_reload_slb(); + handled = 1; + } + return handled; +} + +static long mce_handle_derror_p8(uint64_t dsisr) +{ + return mce_handle_derror(dsisr, P8_DSISR_MC_SLB_ERRORS); +} + +long __machine_check_early_realmode_p8(struct pt_regs *regs) +{ + uint64_t srr1; + long handled = 1; + + srr1 = regs->msr; + + if (P7_SRR1_MC_LOADSTORE(srr1)) + handled = mce_handle_derror_p8(regs->dsisr); + else + handled = mce_handle_ierror_p8(srr1); + + /* TODO: Decode machine check reason. */ + return handled; +}