5.9-stable patches

added patches:
	kvm-arm64-arm_smccc_arch_workaround_1-doesn-t-return-smccc_ret_not_required.patch

diff --git a/queue-5.9/kvm-arm64-arm_smccc_arch_workaround_1-doesn-t-return-smccc_ret_not_required.patch b/queue-5.9/kvm-arm64-arm_smccc_arch_workaround_1-doesn-t-return-smccc_ret_not_required.patch
new file mode 100644 (file)
index 0000000..004aacd
--- /dev/null
+++ b/queue-5.9/kvm-arm64-arm_smccc_arch_workaround_1-doesn-t-return-smccc_ret_not_required.patch
@@ -0,0 +1,83 @@
+From 1de111b51b829bcf01d2e57971f8fd07a665fa3f Mon Sep 17 00:00:00 2001
+From: Stephen Boyd <swboyd@chromium.org>
+Date: Fri, 23 Oct 2020 08:47:50 -0700
+Subject: KVM: arm64: ARM_SMCCC_ARCH_WORKAROUND_1 doesn't return SMCCC_RET_NOT_REQUIRED
+
+From: Stephen Boyd <swboyd@chromium.org>
+
+commit 1de111b51b829bcf01d2e57971f8fd07a665fa3f upstream.
+
+According to the SMCCC spec[1](7.5.2 Discovery) the
+ARM_SMCCC_ARCH_WORKAROUND_1 function id only returns 0, 1, and
+SMCCC_RET_NOT_SUPPORTED.
+
+ 0 is "workaround required and safe to call this function"
+ 1 is "workaround not required but safe to call this function"
+ SMCCC_RET_NOT_SUPPORTED is "might be vulnerable or might not be, who knows, I give up!"
+
+SMCCC_RET_NOT_SUPPORTED might as well mean "workaround required, except
+calling this function may not work because it isn't implemented in some
+cases". Wonderful. We map this SMC call to
+
+ 0 is SPECTRE_MITIGATED
+ 1 is SPECTRE_UNAFFECTED
+ SMCCC_RET_NOT_SUPPORTED is SPECTRE_VULNERABLE
+
+For KVM hypercalls (hvc), we've implemented this function id to return
+SMCCC_RET_NOT_SUPPORTED, 0, and SMCCC_RET_NOT_REQUIRED. One of those
+isn't supposed to be there. Per the code we call
+arm64_get_spectre_v2_state() to figure out what to return for this
+feature discovery call.
+
+ 0 is SPECTRE_MITIGATED
+ SMCCC_RET_NOT_REQUIRED is SPECTRE_UNAFFECTED
+ SMCCC_RET_NOT_SUPPORTED is SPECTRE_VULNERABLE
+
+Let's clean this up so that KVM tells the guest this mapping:
+
+ 0 is SPECTRE_MITIGATED
+ 1 is SPECTRE_UNAFFECTED
+ SMCCC_RET_NOT_SUPPORTED is SPECTRE_VULNERABLE
+
+Note: SMCCC_RET_NOT_AFFECTED is 1 but isn't part of the SMCCC spec
+
+Fixes: c118bbb52743 ("arm64: KVM: Propagate full Spectre v2 workaround state to KVM guests")
+Signed-off-by: Stephen Boyd <swboyd@chromium.org>
+Acked-by: Marc Zyngier <maz@kernel.org>
+Acked-by: Will Deacon <will@kernel.org>
+Cc: Andre Przywara <andre.przywara@arm.com>
+Cc: Steven Price <steven.price@arm.com>
+Cc: Marc Zyngier <maz@kernel.org>
+Cc: stable@vger.kernel.org
+Link: https://developer.arm.com/documentation/den0028/latest [1]
+Link: https://lore.kernel.org/r/20201023154751.1973872-1-swboyd@chromium.org
+Signed-off-by: Will Deacon <will@kernel.org>
+Signed-off-by: Stephen Boyd <swboyd@chromium.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/arm64/kvm/hypercalls.c |    2 +-
+ include/linux/arm-smccc.h   |    2 ++
+ 2 files changed, 3 insertions(+), 1 deletion(-)
+
+--- a/arch/arm64/kvm/hypercalls.c
++++ b/arch/arm64/kvm/hypercalls.c
+@@ -31,7 +31,7 @@ int kvm_hvc_call_handler(struct kvm_vcpu
+                               val = SMCCC_RET_SUCCESS;
+                               break;
+                       case KVM_BP_HARDEN_NOT_REQUIRED:
+-                              val = SMCCC_RET_NOT_REQUIRED;
++                              val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED;
+                               break;
+                       }
+                       break;
+--- a/include/linux/arm-smccc.h
++++ b/include/linux/arm-smccc.h
+@@ -86,6 +86,8 @@
+                          ARM_SMCCC_SMC_32,                            \
+                          0, 0x7fff)
+ 
++#define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED  1
++
+ /* Paravirtualised time calls (defined by ARM DEN0057A) */
+ #define ARM_SMCCC_HV_PV_TIME_FEATURES                         \
+       ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,                 \

diff --git a/queue-5.9/series b/queue-5.9/series
index 239ea3fdc89b9527de249b5635cb08779ac3ff23..a3e575c1ed7cf0cccad0a4767010e541e51e5d68 100644 (file)
--- a/queue-5.9/series
+++ b/queue-5.9/series
@@ -388,3 +388,4 @@ vhost_vdpa-return-efault-if-copy_from_user-fails.patch
 vdpa-mlx5-fix-error-return-in-map_direct_mr.patch
 time-prevent-undefined-behaviour-in-timespec64_to_ns.patch
 time-sched_clock-mark-sched_clock_read_begin-retry-as-notrace.patch
+kvm-arm64-arm_smccc_arch_workaround_1-doesn-t-return-smccc_ret_not_required.patch