From: Sebastian Andrzej Siewior Date: Thu, 26 Jul 2018 09:13:42 +0200 Subject: [PATCH 020/351] arm64: KVM: compute_layout before altenates are applied Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=3e7a19db684d20c99425ab89480c71931f76aed3 compute_layout() is invoked as part of an alternative fixup under stop_machine() and needs a sleeping lock as part of get_random_long(). Invoke compute_layout() before the alternatives are applied. Signed-off-by: Sebastian Andrzej Siewior --- arch/arm64/include/asm/alternative.h | 6 ++++++ arch/arm64/kernel/alternative.c | 1 + arch/arm64/kvm/va_layout.c | 7 +------ 3 files changed, 8 insertions(+), 6 deletions(-) diff --git a/arch/arm64/include/asm/alternative.h b/arch/arm64/include/asm/alternative.h index 4fbbcdda70d7..99b215602a1a 100644 --- a/arch/arm64/include/asm/alternative.h +++ b/arch/arm64/include/asm/alternative.h @@ -35,6 +35,12 @@ void apply_alternatives_module(void *start, size_t length); static inline void apply_alternatives_module(void *start, size_t length) { } #endif +#ifdef CONFIG_KVM_ARM_HOST +void kvm_compute_layout(void); +#else +static inline void kvm_compute_layout(void) { } +#endif + #define ALTINSTR_ENTRY(feature) \ " .word 661b - .\n" /* label */ \ " .word 663f - .\n" /* new instruction */ \ diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c index 3747c8d87bdb..75ccb5b279a2 100644 --- a/arch/arm64/kernel/alternative.c +++ b/arch/arm64/kernel/alternative.c @@ -212,6 +212,7 @@ static int __apply_alternatives_multi_stop(void *unused) void __init apply_alternatives_all(void) { /* better not try code patching on a live SMP system */ + kvm_compute_layout(); stop_machine(__apply_alternatives_multi_stop, NULL, cpu_online_mask); } diff --git a/arch/arm64/kvm/va_layout.c b/arch/arm64/kvm/va_layout.c index c712a7376bc1..792da0e125de 100644 --- a/arch/arm64/kvm/va_layout.c +++ b/arch/arm64/kvm/va_layout.c @@ -33,7 +33,7 @@ static u8 tag_lsb; static u64 tag_val; static u64 va_mask; -static void compute_layout(void) +__init void kvm_compute_layout(void) { phys_addr_t idmap_addr = __pa_symbol(__hyp_idmap_text_start); u64 hyp_va_msb; @@ -121,8 +121,6 @@ void __init kvm_update_va_mask(struct alt_instr *alt, BUG_ON(nr_inst != 5); - if (!has_vhe() && !va_mask) - compute_layout(); for (i = 0; i < nr_inst; i++) { u32 rd, rn, insn, oinsn; @@ -167,9 +165,6 @@ void kvm_patch_vector_branch(struct alt_instr *alt, return; } - if (!va_mask) - compute_layout(); - /* * Compute HYP VA by using the same computation as kern_hyp_va() */