From a6201da34ff9366680e97392efd06abb9ff15014 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Mon, 2 Apr 2018 13:03:37 +0530 Subject: [PATCH] powerpc: Fix oops due to bad access of lppaca on bare metal Commit 8e0b634b1327 ("powerpc/64s: Do not allocate lppaca if we are not virtualized") removed allocation of lppaca on bare metal platforms. But with CONFIG_PPC_SPLPAR enabled, we still access the lppaca on bare metal in some code paths. Fix this but adding runtime checks for SPLPAR (shared processor LPAR). Fixes: 8e0b634b1327 ("powerpc/64s: Do not allocate lppaca if we are not virtualized") Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/lppaca.h | 3 +++ arch/powerpc/include/asm/spinlock.h | 2 ++ arch/powerpc/kernel/time.c | 3 +++ 3 files changed, 8 insertions(+) diff --git a/arch/powerpc/include/asm/lppaca.h b/arch/powerpc/include/asm/lppaca.h index 65d5896..7c23ce8 100644 --- a/arch/powerpc/include/asm/lppaca.h +++ b/arch/powerpc/include/asm/lppaca.h @@ -34,6 +34,7 @@ #include #include #include +#include /* * The lppaca is the "virtual processor area" registered with the hypervisor, @@ -114,6 +115,8 @@ struct lppaca { static inline bool lppaca_shared_proc(struct lppaca *l) { + if (!firmware_has_feature(FW_FEATURE_SPLPAR)) + return false; return !!(l->__old_status & LPPACA_OLD_SHARED_PROC); } diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h index b9ebc30..72dc4dd 100644 --- a/arch/powerpc/include/asm/spinlock.h +++ b/arch/powerpc/include/asm/spinlock.h @@ -56,6 +56,8 @@ #define vcpu_is_preempted vcpu_is_preempted static inline bool vcpu_is_preempted(int cpu) { + if (!firmware_has_feature(FW_FEATURE_SPLPAR)) + return false; return !!(be32_to_cpu(lppaca_of(cpu).yield_count) & 1); } #endif diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index f7d96a6..360e71d 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -266,6 +266,9 @@ void accumulate_stolen_time(void) static inline u64 calculate_stolen_time(u64 stop_tb) { + if (!firmware_has_feature(FW_FEATURE_SPLPAR)) + return 0; + if (get_paca()->dtl_ridx != be64_to_cpu(get_lppaca()->dtl_idx)) return scan_dispatch_log(stop_tb); -- 2.7.4