[PATCH 7/7] powerpc/64s: advertise hardware link stack flush
From: Nicholas Piggin <npiggin@gmail.com>
Date: 2020-06-09 07:41:32
Subsystem:
kernel virtual machine for powerpc (kvm/powerpc), linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
For testing only at the moment, firmware does not define these bits. --- arch/powerpc/include/asm/hvcall.h | 1 + arch/powerpc/include/uapi/asm/kvm.h | 1 + arch/powerpc/kvm/powerpc.c | 9 +++++++-- arch/powerpc/platforms/powernv/setup.c | 3 +++ arch/powerpc/platforms/pseries/setup.c | 3 +++ tools/arch/powerpc/include/uapi/asm/kvm.h | 1 + 6 files changed, 16 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index e90c073e437e..a92a07c89b6f 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h@@ -373,6 +373,7 @@ #define H_CPU_CHAR_THREAD_RECONFIG_CTRL (1ull << 57) // IBM bit 6 #define H_CPU_CHAR_COUNT_CACHE_DISABLED (1ull << 56) // IBM bit 7 #define H_CPU_CHAR_BCCTR_FLUSH_ASSIST (1ull << 54) // IBM bit 9 +#define H_CPU_CHAR_BCCTR_LINK_FLUSH_ASSIST (1ull << 53) // IBM bit 10 #define H_CPU_BEHAV_FAVOUR_SECURITY (1ull << 63) // IBM bit 0 #define H_CPU_BEHAV_L1D_FLUSH_PR (1ull << 62) // IBM bit 1
diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h
index 264e266a85bf..dd229d5f46ee 100644
--- a/arch/powerpc/include/uapi/asm/kvm.h
+++ b/arch/powerpc/include/uapi/asm/kvm.h@@ -464,6 +464,7 @@ struct kvm_ppc_cpu_char { #define KVM_PPC_CPU_CHAR_MTTRIG_THR_RECONF (1ULL << 57) #define KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS (1ULL << 56) #define KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST (1ull << 54) +#define KVM_PPC_CPU_CHAR_BCCTR_LINK_FLUSH_ASSIST (1ull << 53) #define KVM_PPC_CPU_BEHAV_FAVOUR_SECURITY (1ULL << 63) #define KVM_PPC_CPU_BEHAV_L1D_FLUSH_PR (1ULL << 62)
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 27ccff612903..fa981ee09dec 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c@@ -2221,7 +2221,8 @@ static int pseries_get_cpu_char(struct kvm_ppc_cpu_char *cp) KVM_PPC_CPU_CHAR_BR_HINT_HONOURED | KVM_PPC_CPU_CHAR_MTTRIG_THR_RECONF | KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS | - KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST; + KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST | + KVM_PPC_CPU_CHAR_BCCTR_LINK_FLUSH_ASSIST; cp->behaviour_mask = KVM_PPC_CPU_BEHAV_FAVOUR_SECURITY | KVM_PPC_CPU_BEHAV_L1D_FLUSH_PR | KVM_PPC_CPU_BEHAV_BNDS_CHK_SPEC_BAR |
@@ -2287,13 +2288,17 @@ static int kvmppc_get_cpu_char(struct kvm_ppc_cpu_char *cp) if (have_fw_feat(fw_features, "enabled", "fw-count-cache-flush-bcctr2,0,0")) cp->character |= KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST; + if (have_fw_feat(fw_features, "enabled", + "fw-link-stack-flush-bcctr2,0,0")) + cp->character |= KVM_PPC_CPU_CHAR_BCCTR_LINK_FLUSH_ASSIST; cp->character_mask = KVM_PPC_CPU_CHAR_SPEC_BAR_ORI31 | KVM_PPC_CPU_CHAR_BCCTRL_SERIALISED | KVM_PPC_CPU_CHAR_L1D_FLUSH_ORI30 | KVM_PPC_CPU_CHAR_L1D_FLUSH_TRIG2 | KVM_PPC_CPU_CHAR_L1D_THREAD_PRIV | KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS | - KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST; + KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST | + KVM_PPC_CPU_CHAR_BCCTR_LINK_FLUSH_ASSIST; if (have_fw_feat(fw_features, "enabled", "speculation-policy-favor-security"))
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 3bc188da82ba..1a06d3b4c0a9 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c@@ -78,6 +78,9 @@ static void init_fw_feat_flags(struct device_node *np) if (fw_feature_is("enabled", "fw-count-cache-flush-bcctr2,0,0", np)) security_ftr_set(SEC_FTR_BCCTR_FLUSH_ASSIST); + if (fw_feature_is("enabled", "fw-link-stack-flush-bcctr2,0,0", np)) + security_ftr_set(SEC_FTR_BCCTR_LINK_FLUSH_ASSIST); + if (fw_feature_is("enabled", "needs-count-cache-flush-on-context-switch", np)) security_ftr_set(SEC_FTR_FLUSH_COUNT_CACHE);
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 64d18f4bf093..70c9264f23c5 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c@@ -517,6 +517,9 @@ static void init_cpu_char_feature_flags(struct h_cpu_char_result *result) if (result->character & H_CPU_CHAR_BCCTR_FLUSH_ASSIST) security_ftr_set(SEC_FTR_BCCTR_FLUSH_ASSIST); + if (result->character & H_CPU_CHAR_BCCTR_LINK_FLUSH_ASSIST) + security_ftr_set(SEC_FTR_BCCTR_LINK_FLUSH_ASSIST); + if (result->behaviour & H_CPU_BEHAV_FLUSH_COUNT_CACHE) security_ftr_set(SEC_FTR_FLUSH_COUNT_CACHE);
diff --git a/tools/arch/powerpc/include/uapi/asm/kvm.h b/tools/arch/powerpc/include/uapi/asm/kvm.h
index 264e266a85bf..dd229d5f46ee 100644
--- a/tools/arch/powerpc/include/uapi/asm/kvm.h
+++ b/tools/arch/powerpc/include/uapi/asm/kvm.h@@ -464,6 +464,7 @@ struct kvm_ppc_cpu_char { #define KVM_PPC_CPU_CHAR_MTTRIG_THR_RECONF (1ULL << 57) #define KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS (1ULL << 56) #define KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST (1ull << 54) +#define KVM_PPC_CPU_CHAR_BCCTR_LINK_FLUSH_ASSIST (1ull << 53) #define KVM_PPC_CPU_BEHAV_FAVOUR_SECURITY (1ULL << 63) #define KVM_PPC_CPU_BEHAV_L1D_FLUSH_PR (1ULL << 62)
--
2.23.0