December 2024 - Linux-stable-mirror

FAILED: patch "[PATCH] KVM: arm64: vgic-its: Clear DTE when MAPD unmaps a device" failed to apply to 4.19-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x e9649129d33dca561305fc590a7c4ba8c3e5675a # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120253-crawling-traverse-68fd@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From e9649129d33dca561305fc590a7c4ba8c3e5675a Mon Sep 17 00:00:00 2001 From: Kunkun Jiang <jiangkunkun(a)huawei.com> Date: Thu, 7 Nov 2024 13:41:36 -0800 Subject: [PATCH] KVM: arm64: vgic-its: Clear DTE when MAPD unmaps a device vgic_its_save_device_tables will traverse its->device_list to save DTE for each device. vgic_its_restore_device_tables will traverse each entry of device table and check if it is valid. Restore if valid. But when MAPD unmaps a device, it does not invalidate the corresponding DTE. In the scenario of continuous saves and restores, there may be a situation where a device's DTE is not saved but is restored. This is unreasonable and may cause restore to fail. This patch clears the corresponding DTE when MAPD unmaps a device. Cc: stable(a)vger.kernel.org Fixes: 57a9a117154c ("KVM: arm64: vgic-its: Device table save/restore") Co-developed-by: Shusen Li <lishusen2(a)huawei.com> Signed-off-by: Shusen Li <lishusen2(a)huawei.com> Signed-off-by: Kunkun Jiang <jiangkunkun(a)huawei.com> [Jing: Update with entry write helper] Signed-off-by: Jing Zhang <jingzhangos(a)google.com> Link: https://lore.kernel.org/r/20241107214137.428439-5-jingzhangos@google.com Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 68ba7e2453cd..b77fa99eafed 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -1139,9 +1139,11 @@ static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its, bool valid = its_cmd_get_validbit(its_cmd); u8 num_eventid_bits = its_cmd_get_size(its_cmd); gpa_t itt_addr = its_cmd_get_ittaddr(its_cmd); + int dte_esz = vgic_its_get_abi(its)->dte_esz; struct its_device *device; + gpa_t gpa; - if (!vgic_its_check_id(its, its->baser_device_table, device_id, NULL)) + if (!vgic_its_check_id(its, its->baser_device_table, device_id, &gpa)) return E_ITS_MAPD_DEVICE_OOR; if (valid && num_eventid_bits > VITS_TYPER_IDBITS) @@ -1162,7 +1164,7 @@ static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its, * is an error, so we are done in any case. */ if (!valid) - return 0; + return vgic_its_write_entry_lock(its, gpa, 0, dte_esz); device = vgic_its_alloc_device(its, device_id, itt_addr, num_eventid_bits);

4 months, 2 weeks

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FAILED: patch "[PATCH] KVM: arm64: vgic-its: Clear DTE when MAPD unmaps a device" failed to apply to 5.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x e9649129d33dca561305fc590a7c4ba8c3e5675a # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120252-submersed-reorder-64c3@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From e9649129d33dca561305fc590a7c4ba8c3e5675a Mon Sep 17 00:00:00 2001 From: Kunkun Jiang <jiangkunkun(a)huawei.com> Date: Thu, 7 Nov 2024 13:41:36 -0800 Subject: [PATCH] KVM: arm64: vgic-its: Clear DTE when MAPD unmaps a device vgic_its_save_device_tables will traverse its->device_list to save DTE for each device. vgic_its_restore_device_tables will traverse each entry of device table and check if it is valid. Restore if valid. But when MAPD unmaps a device, it does not invalidate the corresponding DTE. In the scenario of continuous saves and restores, there may be a situation where a device's DTE is not saved but is restored. This is unreasonable and may cause restore to fail. This patch clears the corresponding DTE when MAPD unmaps a device. Cc: stable(a)vger.kernel.org Fixes: 57a9a117154c ("KVM: arm64: vgic-its: Device table save/restore") Co-developed-by: Shusen Li <lishusen2(a)huawei.com> Signed-off-by: Shusen Li <lishusen2(a)huawei.com> Signed-off-by: Kunkun Jiang <jiangkunkun(a)huawei.com> [Jing: Update with entry write helper] Signed-off-by: Jing Zhang <jingzhangos(a)google.com> Link: https://lore.kernel.org/r/20241107214137.428439-5-jingzhangos@google.com Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 68ba7e2453cd..b77fa99eafed 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -1139,9 +1139,11 @@ static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its, bool valid = its_cmd_get_validbit(its_cmd); u8 num_eventid_bits = its_cmd_get_size(its_cmd); gpa_t itt_addr = its_cmd_get_ittaddr(its_cmd); + int dte_esz = vgic_its_get_abi(its)->dte_esz; struct its_device *device; + gpa_t gpa; - if (!vgic_its_check_id(its, its->baser_device_table, device_id, NULL)) + if (!vgic_its_check_id(its, its->baser_device_table, device_id, &gpa)) return E_ITS_MAPD_DEVICE_OOR; if (valid && num_eventid_bits > VITS_TYPER_IDBITS) @@ -1162,7 +1164,7 @@ static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its, * is an error, so we are done in any case. */ if (!valid) - return 0; + return vgic_its_write_entry_lock(its, gpa, 0, dte_esz); device = vgic_its_alloc_device(its, device_id, itt_addr, num_eventid_bits);

4 months, 2 weeks

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FAILED: patch "[PATCH] KVM: arm64: vgic-its: Clear ITE when DISCARD frees an ITE" failed to apply to 4.19-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x 7602ffd1d5e8927fadd5187cb4aed2fdc9c47143 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120229-transfer-capped-7af1@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 7602ffd1d5e8927fadd5187cb4aed2fdc9c47143 Mon Sep 17 00:00:00 2001 From: Kunkun Jiang <jiangkunkun(a)huawei.com> Date: Thu, 7 Nov 2024 13:41:37 -0800 Subject: [PATCH] KVM: arm64: vgic-its: Clear ITE when DISCARD frees an ITE When DISCARD frees an ITE, it does not invalidate the corresponding ITE. In the scenario of continuous saves and restores, there may be a situation where an ITE is not saved but is restored. This is unreasonable and may cause restore to fail. This patch clears the corresponding ITE when DISCARD frees an ITE. Cc: stable(a)vger.kernel.org Fixes: eff484e0298d ("KVM: arm64: vgic-its: ITT save and restore") Signed-off-by: Kunkun Jiang <jiangkunkun(a)huawei.com> [Jing: Update with entry write helper] Signed-off-by: Jing Zhang <jingzhangos(a)google.com> Link: https://lore.kernel.org/r/20241107214137.428439-6-jingzhangos@google.com Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index b77fa99eafed..198296933e7e 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -782,6 +782,9 @@ static int vgic_its_cmd_handle_discard(struct kvm *kvm, struct vgic_its *its, ite = find_ite(its, device_id, event_id); if (ite && its_is_collection_mapped(ite->collection)) { + struct its_device *device = find_its_device(its, device_id); + int ite_esz = vgic_its_get_abi(its)->ite_esz; + gpa_t gpa = device->itt_addr + ite->event_id * ite_esz; /* * Though the spec talks about removing the pending state, we * don't bother here since we clear the ITTE anyway and the @@ -790,7 +793,8 @@ static int vgic_its_cmd_handle_discard(struct kvm *kvm, struct vgic_its *its, vgic_its_invalidate_cache(its); its_free_ite(kvm, ite); - return 0; + + return vgic_its_write_entry_lock(its, gpa, 0, ite_esz); } return E_ITS_DISCARD_UNMAPPED_INTERRUPT;

4 months, 2 weeks

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FAILED: patch "[PATCH] KVM: arm64: vgic-its: Clear ITE when DISCARD frees an ITE" failed to apply to 5.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x 7602ffd1d5e8927fadd5187cb4aed2fdc9c47143 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120229-backshift-recolor-5b9b@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 7602ffd1d5e8927fadd5187cb4aed2fdc9c47143 Mon Sep 17 00:00:00 2001 From: Kunkun Jiang <jiangkunkun(a)huawei.com> Date: Thu, 7 Nov 2024 13:41:37 -0800 Subject: [PATCH] KVM: arm64: vgic-its: Clear ITE when DISCARD frees an ITE When DISCARD frees an ITE, it does not invalidate the corresponding ITE. In the scenario of continuous saves and restores, there may be a situation where an ITE is not saved but is restored. This is unreasonable and may cause restore to fail. This patch clears the corresponding ITE when DISCARD frees an ITE. Cc: stable(a)vger.kernel.org Fixes: eff484e0298d ("KVM: arm64: vgic-its: ITT save and restore") Signed-off-by: Kunkun Jiang <jiangkunkun(a)huawei.com> [Jing: Update with entry write helper] Signed-off-by: Jing Zhang <jingzhangos(a)google.com> Link: https://lore.kernel.org/r/20241107214137.428439-6-jingzhangos@google.com Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index b77fa99eafed..198296933e7e 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -782,6 +782,9 @@ static int vgic_its_cmd_handle_discard(struct kvm *kvm, struct vgic_its *its, ite = find_ite(its, device_id, event_id); if (ite && its_is_collection_mapped(ite->collection)) { + struct its_device *device = find_its_device(its, device_id); + int ite_esz = vgic_its_get_abi(its)->ite_esz; + gpa_t gpa = device->itt_addr + ite->event_id * ite_esz; /* * Though the spec talks about removing the pending state, we * don't bother here since we clear the ITTE anyway and the @@ -790,7 +793,8 @@ static int vgic_its_cmd_handle_discard(struct kvm *kvm, struct vgic_its *its, vgic_its_invalidate_cache(its); its_free_ite(kvm, ite); - return 0; + + return vgic_its_write_entry_lock(its, gpa, 0, ite_esz); } return E_ITS_DISCARD_UNMAPPED_INTERRUPT;

4 months, 2 weeks

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FAILED: patch "[PATCH] KVM: arm64: Don't retire aborted MMIO instruction" failed to apply to 5.10-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x e735a5da64420a86be370b216c269b5dd8e830e2 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120209-cranberry-font-7473@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From e735a5da64420a86be370b216c269b5dd8e830e2 Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Fri, 25 Oct 2024 20:31:03 +0000 Subject: [PATCH] KVM: arm64: Don't retire aborted MMIO instruction Returning an abort to the guest for an unsupported MMIO access is a documented feature of the KVM UAPI. Nevertheless, it's clear that this plumbing has seen limited testing, since userspace can trivially cause a WARN in the MMIO return: WARNING: CPU: 0 PID: 30558 at arch/arm64/include/asm/kvm_emulate.h:536 kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 Call trace: kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 kvm_arch_vcpu_ioctl_run+0x98/0x15b4 arch/arm64/kvm/arm.c:1133 kvm_vcpu_ioctl+0x75c/0xa78 virt/kvm/kvm_main.c:4487 __do_sys_ioctl fs/ioctl.c:51 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x1e0/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x38/0x68 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x90/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 The splat is complaining that KVM is advancing PC while an exception is pending, i.e. that KVM is retiring the MMIO instruction despite a pending synchronous external abort. Womp womp. Fix the glaring UAPI bug by skipping over all the MMIO emulation in case there is a pending synchronous exception. Note that while userspace is capable of pending an asynchronous exception (SError, IRQ, or FIQ), it is still safe to retire the MMIO instruction in this case as (1) they are by definition asynchronous, and (2) KVM relies on hardware support for pending/delivering these exceptions instead of the software state machine for advancing PC. Cc: stable(a)vger.kernel.org Fixes: da345174ceca ("KVM: arm/arm64: Allow user injection of external data aborts") Reported-by: Alexander Potapenko <glider(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Link: https://lore.kernel.org/r/20241025203106.3529261-2-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c index cd6b7b83e2c3..ab365e839874 100644 --- a/arch/arm64/kvm/mmio.c +++ b/arch/arm64/kvm/mmio.c @@ -72,6 +72,31 @@ unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len) return data; } +static bool kvm_pending_sync_exception(struct kvm_vcpu *vcpu) +{ + if (!vcpu_get_flag(vcpu, PENDING_EXCEPTION)) + return false; + + if (vcpu_el1_is_32bit(vcpu)) { + switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) { + case unpack_vcpu_flag(EXCEPT_AA32_UND): + case unpack_vcpu_flag(EXCEPT_AA32_IABT): + case unpack_vcpu_flag(EXCEPT_AA32_DABT): + return true; + default: + return false; + } + } else { + switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) { + case unpack_vcpu_flag(EXCEPT_AA64_EL1_SYNC): + case unpack_vcpu_flag(EXCEPT_AA64_EL2_SYNC): + return true; + default: + return false; + } + } +} + /** * kvm_handle_mmio_return -- Handle MMIO loads after user space emulation * or in-kernel IO emulation @@ -84,8 +109,11 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu) unsigned int len; int mask; - /* Detect an already handled MMIO return */ - if (unlikely(!vcpu->mmio_needed)) + /* + * Detect if the MMIO return was already handled or if userspace aborted + * the MMIO access. + */ + if (unlikely(!vcpu->mmio_needed || kvm_pending_sync_exception(vcpu))) return 1; vcpu->mmio_needed = 0;

4 months, 2 weeks

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FAILED: patch "[PATCH] KVM: arm64: Don't retire aborted MMIO instruction" failed to apply to 5.15-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x e735a5da64420a86be370b216c269b5dd8e830e2 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120208-mundane-finite-682f@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From e735a5da64420a86be370b216c269b5dd8e830e2 Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Fri, 25 Oct 2024 20:31:03 +0000 Subject: [PATCH] KVM: arm64: Don't retire aborted MMIO instruction Returning an abort to the guest for an unsupported MMIO access is a documented feature of the KVM UAPI. Nevertheless, it's clear that this plumbing has seen limited testing, since userspace can trivially cause a WARN in the MMIO return: WARNING: CPU: 0 PID: 30558 at arch/arm64/include/asm/kvm_emulate.h:536 kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 Call trace: kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 kvm_arch_vcpu_ioctl_run+0x98/0x15b4 arch/arm64/kvm/arm.c:1133 kvm_vcpu_ioctl+0x75c/0xa78 virt/kvm/kvm_main.c:4487 __do_sys_ioctl fs/ioctl.c:51 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x1e0/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x38/0x68 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x90/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 The splat is complaining that KVM is advancing PC while an exception is pending, i.e. that KVM is retiring the MMIO instruction despite a pending synchronous external abort. Womp womp. Fix the glaring UAPI bug by skipping over all the MMIO emulation in case there is a pending synchronous exception. Note that while userspace is capable of pending an asynchronous exception (SError, IRQ, or FIQ), it is still safe to retire the MMIO instruction in this case as (1) they are by definition asynchronous, and (2) KVM relies on hardware support for pending/delivering these exceptions instead of the software state machine for advancing PC. Cc: stable(a)vger.kernel.org Fixes: da345174ceca ("KVM: arm/arm64: Allow user injection of external data aborts") Reported-by: Alexander Potapenko <glider(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Link: https://lore.kernel.org/r/20241025203106.3529261-2-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c index cd6b7b83e2c3..ab365e839874 100644 --- a/arch/arm64/kvm/mmio.c +++ b/arch/arm64/kvm/mmio.c @@ -72,6 +72,31 @@ unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len) return data; } +static bool kvm_pending_sync_exception(struct kvm_vcpu *vcpu) +{ + if (!vcpu_get_flag(vcpu, PENDING_EXCEPTION)) + return false; + + if (vcpu_el1_is_32bit(vcpu)) { + switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) { + case unpack_vcpu_flag(EXCEPT_AA32_UND): + case unpack_vcpu_flag(EXCEPT_AA32_IABT): + case unpack_vcpu_flag(EXCEPT_AA32_DABT): + return true; + default: + return false; + } + } else { + switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) { + case unpack_vcpu_flag(EXCEPT_AA64_EL1_SYNC): + case unpack_vcpu_flag(EXCEPT_AA64_EL2_SYNC): + return true; + default: + return false; + } + } +} + /** * kvm_handle_mmio_return -- Handle MMIO loads after user space emulation * or in-kernel IO emulation @@ -84,8 +109,11 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu) unsigned int len; int mask; - /* Detect an already handled MMIO return */ - if (unlikely(!vcpu->mmio_needed)) + /* + * Detect if the MMIO return was already handled or if userspace aborted + * the MMIO access. + */ + if (unlikely(!vcpu->mmio_needed || kvm_pending_sync_exception(vcpu))) return 1; vcpu->mmio_needed = 0;

4 months, 2 weeks

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FAILED: patch "[PATCH] KVM: arm64: Don't retire aborted MMIO instruction" failed to apply to 6.1-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x e735a5da64420a86be370b216c269b5dd8e830e2 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120207-banker-blast-f652@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From e735a5da64420a86be370b216c269b5dd8e830e2 Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Fri, 25 Oct 2024 20:31:03 +0000 Subject: [PATCH] KVM: arm64: Don't retire aborted MMIO instruction Returning an abort to the guest for an unsupported MMIO access is a documented feature of the KVM UAPI. Nevertheless, it's clear that this plumbing has seen limited testing, since userspace can trivially cause a WARN in the MMIO return: WARNING: CPU: 0 PID: 30558 at arch/arm64/include/asm/kvm_emulate.h:536 kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 Call trace: kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 kvm_arch_vcpu_ioctl_run+0x98/0x15b4 arch/arm64/kvm/arm.c:1133 kvm_vcpu_ioctl+0x75c/0xa78 virt/kvm/kvm_main.c:4487 __do_sys_ioctl fs/ioctl.c:51 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x1e0/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x38/0x68 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x90/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 The splat is complaining that KVM is advancing PC while an exception is pending, i.e. that KVM is retiring the MMIO instruction despite a pending synchronous external abort. Womp womp. Fix the glaring UAPI bug by skipping over all the MMIO emulation in case there is a pending synchronous exception. Note that while userspace is capable of pending an asynchronous exception (SError, IRQ, or FIQ), it is still safe to retire the MMIO instruction in this case as (1) they are by definition asynchronous, and (2) KVM relies on hardware support for pending/delivering these exceptions instead of the software state machine for advancing PC. Cc: stable(a)vger.kernel.org Fixes: da345174ceca ("KVM: arm/arm64: Allow user injection of external data aborts") Reported-by: Alexander Potapenko <glider(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Link: https://lore.kernel.org/r/20241025203106.3529261-2-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c index cd6b7b83e2c3..ab365e839874 100644 --- a/arch/arm64/kvm/mmio.c +++ b/arch/arm64/kvm/mmio.c @@ -72,6 +72,31 @@ unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len) return data; } +static bool kvm_pending_sync_exception(struct kvm_vcpu *vcpu) +{ + if (!vcpu_get_flag(vcpu, PENDING_EXCEPTION)) + return false; + + if (vcpu_el1_is_32bit(vcpu)) { + switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) { + case unpack_vcpu_flag(EXCEPT_AA32_UND): + case unpack_vcpu_flag(EXCEPT_AA32_IABT): + case unpack_vcpu_flag(EXCEPT_AA32_DABT): + return true; + default: + return false; + } + } else { + switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) { + case unpack_vcpu_flag(EXCEPT_AA64_EL1_SYNC): + case unpack_vcpu_flag(EXCEPT_AA64_EL2_SYNC): + return true; + default: + return false; + } + } +} + /** * kvm_handle_mmio_return -- Handle MMIO loads after user space emulation * or in-kernel IO emulation @@ -84,8 +109,11 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu) unsigned int len; int mask; - /* Detect an already handled MMIO return */ - if (unlikely(!vcpu->mmio_needed)) + /* + * Detect if the MMIO return was already handled or if userspace aborted + * the MMIO access. + */ + if (unlikely(!vcpu->mmio_needed || kvm_pending_sync_exception(vcpu))) return 1; vcpu->mmio_needed = 0;

4 months, 2 weeks

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FAILED: patch "[PATCH] KVM: arm64: Don't retire aborted MMIO instruction" failed to apply to 6.6-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x e735a5da64420a86be370b216c269b5dd8e830e2 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120206-conflict-ambiguity-0106@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From e735a5da64420a86be370b216c269b5dd8e830e2 Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Fri, 25 Oct 2024 20:31:03 +0000 Subject: [PATCH] KVM: arm64: Don't retire aborted MMIO instruction Returning an abort to the guest for an unsupported MMIO access is a documented feature of the KVM UAPI. Nevertheless, it's clear that this plumbing has seen limited testing, since userspace can trivially cause a WARN in the MMIO return: WARNING: CPU: 0 PID: 30558 at arch/arm64/include/asm/kvm_emulate.h:536 kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 Call trace: kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 kvm_arch_vcpu_ioctl_run+0x98/0x15b4 arch/arm64/kvm/arm.c:1133 kvm_vcpu_ioctl+0x75c/0xa78 virt/kvm/kvm_main.c:4487 __do_sys_ioctl fs/ioctl.c:51 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x1e0/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x38/0x68 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x90/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 The splat is complaining that KVM is advancing PC while an exception is pending, i.e. that KVM is retiring the MMIO instruction despite a pending synchronous external abort. Womp womp. Fix the glaring UAPI bug by skipping over all the MMIO emulation in case there is a pending synchronous exception. Note that while userspace is capable of pending an asynchronous exception (SError, IRQ, or FIQ), it is still safe to retire the MMIO instruction in this case as (1) they are by definition asynchronous, and (2) KVM relies on hardware support for pending/delivering these exceptions instead of the software state machine for advancing PC. Cc: stable(a)vger.kernel.org Fixes: da345174ceca ("KVM: arm/arm64: Allow user injection of external data aborts") Reported-by: Alexander Potapenko <glider(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Link: https://lore.kernel.org/r/20241025203106.3529261-2-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c index cd6b7b83e2c3..ab365e839874 100644 --- a/arch/arm64/kvm/mmio.c +++ b/arch/arm64/kvm/mmio.c @@ -72,6 +72,31 @@ unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len) return data; } +static bool kvm_pending_sync_exception(struct kvm_vcpu *vcpu) +{ + if (!vcpu_get_flag(vcpu, PENDING_EXCEPTION)) + return false; + + if (vcpu_el1_is_32bit(vcpu)) { + switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) { + case unpack_vcpu_flag(EXCEPT_AA32_UND): + case unpack_vcpu_flag(EXCEPT_AA32_IABT): + case unpack_vcpu_flag(EXCEPT_AA32_DABT): + return true; + default: + return false; + } + } else { + switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) { + case unpack_vcpu_flag(EXCEPT_AA64_EL1_SYNC): + case unpack_vcpu_flag(EXCEPT_AA64_EL2_SYNC): + return true; + default: + return false; + } + } +} + /** * kvm_handle_mmio_return -- Handle MMIO loads after user space emulation * or in-kernel IO emulation @@ -84,8 +109,11 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu) unsigned int len; int mask; - /* Detect an already handled MMIO return */ - if (unlikely(!vcpu->mmio_needed)) + /* + * Detect if the MMIO return was already handled or if userspace aborted + * the MMIO access. + */ + if (unlikely(!vcpu->mmio_needed || kvm_pending_sync_exception(vcpu))) return 1; vcpu->mmio_needed = 0;

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FAILED: patch "[PATCH] Revert "KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata" failed to apply to 6.1-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 85434c3c73fcad58870016ddfe5eaa5036672675 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120245-frighten-linseed-1821@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 85434c3c73fcad58870016ddfe5eaa5036672675 Mon Sep 17 00:00:00 2001 From: Sean Christopherson <seanjc(a)google.com> Date: Mon, 18 Nov 2024 17:14:33 -0800 Subject: [PATCH] Revert "KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()" Revert back to clearing VM_{ENTRY,EXIT}_LOAD_IA32_PERF_GLOBAL_CTRL in KVM's golden VMCS config, as applying the workaround during vCPU creation is pointless and broken. KVM *unconditionally* clears the controls in the values returned by vmx_vmentry_ctrl() and vmx_vmexit_ctrl(), as KVM loads PERF_GLOBAL_CTRL if and only if its necessary to do so. E.g. if KVM wants to run the guest with the same PERF_GLOBAL_CTRL as the host, then there's no need to re-load the MSR on entry and exit. Even worse, the buggy commit failed to apply the erratum where it's actually needed, add_atomic_switch_msr(). As a result, KVM completely ignores the erratum for all intents and purposes, i.e. uses the flawed VMCS controls to load PERF_GLOBAL_CTRL. To top things off, the patch was intended to be dropped, as the premise of an L1 VMM being able to pivot on FMS is flawed, and KVM can (and now does) fully emulate the controls in software. Simply revert the commit, as all upstream supported kernels that have the buggy commit should also have commit f4c93d1a0e71 ("KVM: nVMX: Always emulate PERF_GLOBAL_CTRL VM-Entry/VM-Exit controls"), i.e. the (likely theoretical) live migration concern is a complete non-issue. Opportunistically drop the manual "kvm: " scope from the warning about the erratum, as KVM now uses pr_fmt() to provide the correct scope (v6.1 kernels and earlier don't, but the erratum only applies to CPUs that are 15+ years old; it's not worth a separate patch). This reverts commit 9d78d6fb186bc4aff41b5d6c4726b76649d3cb53. Link: https://lore.kernel.org/all/YtnZmCutdd5tpUmz@google.com Fixes: 9d78d6fb186b ("KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()") Cc: stable(a)vger.kernel.org Cc: Vitaly Kuznetsov <vkuznets(a)redhat.com> Cc: Maxim Levitsky <mlevitsk(a)redhat.com> Signed-off-by: Sean Christopherson <seanjc(a)google.com> Reviewed-by: Vitaly Kuznetsov <vkuznets(a)redhat.com> Message-ID: <20241119011433.1797921-1-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 0f008f5ef6f0..893366e53732 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2548,28 +2548,6 @@ static bool cpu_has_sgx(void) return cpuid_eax(0) >= 0x12 && (cpuid_eax(0x12) & BIT(0)); } -/* - * Some cpus support VM_{ENTRY,EXIT}_IA32_PERF_GLOBAL_CTRL but they - * can't be used due to errata where VM Exit may incorrectly clear - * IA32_PERF_GLOBAL_CTRL[34:32]. Work around the errata by using the - * MSR load mechanism to switch IA32_PERF_GLOBAL_CTRL. - */ -static bool cpu_has_perf_global_ctrl_bug(void) -{ - switch (boot_cpu_data.x86_vfm) { - case INTEL_NEHALEM_EP: /* AAK155 */ - case INTEL_NEHALEM: /* AAP115 */ - case INTEL_WESTMERE: /* AAT100 */ - case INTEL_WESTMERE_EP: /* BC86,AAY89,BD102 */ - case INTEL_NEHALEM_EX: /* BA97 */ - return true; - default: - break; - } - - return false; -} - static int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, u32 msr, u32 *result) { u32 vmx_msr_low, vmx_msr_high; @@ -2729,6 +2707,27 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf, _vmexit_control &= ~x_ctrl; } + /* + * Some cpus support VM_{ENTRY,EXIT}_IA32_PERF_GLOBAL_CTRL but they + * can't be used due to an errata where VM Exit may incorrectly clear + * IA32_PERF_GLOBAL_CTRL[34:32]. Workaround the errata by using the + * MSR load mechanism to switch IA32_PERF_GLOBAL_CTRL. + */ + switch (boot_cpu_data.x86_vfm) { + case INTEL_NEHALEM_EP: /* AAK155 */ + case INTEL_NEHALEM: /* AAP115 */ + case INTEL_WESTMERE: /* AAT100 */ + case INTEL_WESTMERE_EP: /* BC86,AAY89,BD102 */ + case INTEL_NEHALEM_EX: /* BA97 */ + _vmentry_control &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL; + _vmexit_control &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL; + pr_warn_once("VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL " + "does not work properly. Using workaround\n"); + break; + default: + break; + } + rdmsrl(MSR_IA32_VMX_BASIC, basic_msr); /* IA-32 SDM Vol 3B: VMCS size is never greater than 4kB. */ @@ -4432,9 +4431,6 @@ static u32 vmx_vmentry_ctrl(void) VM_ENTRY_LOAD_IA32_EFER | VM_ENTRY_IA32E_MODE); - if (cpu_has_perf_global_ctrl_bug()) - vmentry_ctrl &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL; - return vmentry_ctrl; } @@ -4452,10 +4448,6 @@ static u32 vmx_vmexit_ctrl(void) if (vmx_pt_mode_is_system()) vmexit_ctrl &= ~(VM_EXIT_PT_CONCEAL_PIP | VM_EXIT_CLEAR_IA32_RTIT_CTL); - - if (cpu_has_perf_global_ctrl_bug()) - vmexit_ctrl &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL; - /* Loading of EFER and PERF_GLOBAL_CTRL are toggled dynamically */ return vmexit_ctrl & ~(VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL | VM_EXIT_LOAD_IA32_EFER); @@ -8415,10 +8407,6 @@ __init int vmx_hardware_setup(void) if (setup_vmcs_config(&vmcs_config, &vmx_capability) < 0) return -EIO; - if (cpu_has_perf_global_ctrl_bug()) - pr_warn_once("VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL " - "does not work properly. Using workaround\n"); - if (boot_cpu_has(X86_FEATURE_NX)) kvm_enable_efer_bits(EFER_NX);

4 months, 2 weeks

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FAILED: patch "[PATCH] Revert "KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata" failed to apply to 6.6-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 85434c3c73fcad58870016ddfe5eaa5036672675 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024120244-luxury-rebirth-25fd@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 85434c3c73fcad58870016ddfe5eaa5036672675 Mon Sep 17 00:00:00 2001 From: Sean Christopherson <seanjc(a)google.com> Date: Mon, 18 Nov 2024 17:14:33 -0800 Subject: [PATCH] Revert "KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()" Revert back to clearing VM_{ENTRY,EXIT}_LOAD_IA32_PERF_GLOBAL_CTRL in KVM's golden VMCS config, as applying the workaround during vCPU creation is pointless and broken. KVM *unconditionally* clears the controls in the values returned by vmx_vmentry_ctrl() and vmx_vmexit_ctrl(), as KVM loads PERF_GLOBAL_CTRL if and only if its necessary to do so. E.g. if KVM wants to run the guest with the same PERF_GLOBAL_CTRL as the host, then there's no need to re-load the MSR on entry and exit. Even worse, the buggy commit failed to apply the erratum where it's actually needed, add_atomic_switch_msr(). As a result, KVM completely ignores the erratum for all intents and purposes, i.e. uses the flawed VMCS controls to load PERF_GLOBAL_CTRL. To top things off, the patch was intended to be dropped, as the premise of an L1 VMM being able to pivot on FMS is flawed, and KVM can (and now does) fully emulate the controls in software. Simply revert the commit, as all upstream supported kernels that have the buggy commit should also have commit f4c93d1a0e71 ("KVM: nVMX: Always emulate PERF_GLOBAL_CTRL VM-Entry/VM-Exit controls"), i.e. the (likely theoretical) live migration concern is a complete non-issue. Opportunistically drop the manual "kvm: " scope from the warning about the erratum, as KVM now uses pr_fmt() to provide the correct scope (v6.1 kernels and earlier don't, but the erratum only applies to CPUs that are 15+ years old; it's not worth a separate patch). This reverts commit 9d78d6fb186bc4aff41b5d6c4726b76649d3cb53. Link: https://lore.kernel.org/all/YtnZmCutdd5tpUmz@google.com Fixes: 9d78d6fb186b ("KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()") Cc: stable(a)vger.kernel.org Cc: Vitaly Kuznetsov <vkuznets(a)redhat.com> Cc: Maxim Levitsky <mlevitsk(a)redhat.com> Signed-off-by: Sean Christopherson <seanjc(a)google.com> Reviewed-by: Vitaly Kuznetsov <vkuznets(a)redhat.com> Message-ID: <20241119011433.1797921-1-seanjc(a)google.com> Signed-off-by: Paolo Bonzini <pbonzini(a)redhat.com> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 0f008f5ef6f0..893366e53732 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2548,28 +2548,6 @@ static bool cpu_has_sgx(void) return cpuid_eax(0) >= 0x12 && (cpuid_eax(0x12) & BIT(0)); } -/* - * Some cpus support VM_{ENTRY,EXIT}_IA32_PERF_GLOBAL_CTRL but they - * can't be used due to errata where VM Exit may incorrectly clear - * IA32_PERF_GLOBAL_CTRL[34:32]. Work around the errata by using the - * MSR load mechanism to switch IA32_PERF_GLOBAL_CTRL. - */ -static bool cpu_has_perf_global_ctrl_bug(void) -{ - switch (boot_cpu_data.x86_vfm) { - case INTEL_NEHALEM_EP: /* AAK155 */ - case INTEL_NEHALEM: /* AAP115 */ - case INTEL_WESTMERE: /* AAT100 */ - case INTEL_WESTMERE_EP: /* BC86,AAY89,BD102 */ - case INTEL_NEHALEM_EX: /* BA97 */ - return true; - default: - break; - } - - return false; -} - static int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, u32 msr, u32 *result) { u32 vmx_msr_low, vmx_msr_high; @@ -2729,6 +2707,27 @@ static int setup_vmcs_config(struct vmcs_config *vmcs_conf, _vmexit_control &= ~x_ctrl; } + /* + * Some cpus support VM_{ENTRY,EXIT}_IA32_PERF_GLOBAL_CTRL but they + * can't be used due to an errata where VM Exit may incorrectly clear + * IA32_PERF_GLOBAL_CTRL[34:32]. Workaround the errata by using the + * MSR load mechanism to switch IA32_PERF_GLOBAL_CTRL. + */ + switch (boot_cpu_data.x86_vfm) { + case INTEL_NEHALEM_EP: /* AAK155 */ + case INTEL_NEHALEM: /* AAP115 */ + case INTEL_WESTMERE: /* AAT100 */ + case INTEL_WESTMERE_EP: /* BC86,AAY89,BD102 */ + case INTEL_NEHALEM_EX: /* BA97 */ + _vmentry_control &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL; + _vmexit_control &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL; + pr_warn_once("VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL " + "does not work properly. Using workaround\n"); + break; + default: + break; + } + rdmsrl(MSR_IA32_VMX_BASIC, basic_msr); /* IA-32 SDM Vol 3B: VMCS size is never greater than 4kB. */ @@ -4432,9 +4431,6 @@ static u32 vmx_vmentry_ctrl(void) VM_ENTRY_LOAD_IA32_EFER | VM_ENTRY_IA32E_MODE); - if (cpu_has_perf_global_ctrl_bug()) - vmentry_ctrl &= ~VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL; - return vmentry_ctrl; } @@ -4452,10 +4448,6 @@ static u32 vmx_vmexit_ctrl(void) if (vmx_pt_mode_is_system()) vmexit_ctrl &= ~(VM_EXIT_PT_CONCEAL_PIP | VM_EXIT_CLEAR_IA32_RTIT_CTL); - - if (cpu_has_perf_global_ctrl_bug()) - vmexit_ctrl &= ~VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL; - /* Loading of EFER and PERF_GLOBAL_CTRL are toggled dynamically */ return vmexit_ctrl & ~(VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL | VM_EXIT_LOAD_IA32_EFER); @@ -8415,10 +8407,6 @@ __init int vmx_hardware_setup(void) if (setup_vmcs_config(&vmcs_config, &vmx_capability) < 0) return -EIO; - if (cpu_has_perf_global_ctrl_bug()) - pr_warn_once("VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL " - "does not work properly. Using workaround\n"); - if (boot_cpu_has(X86_FEATURE_NX)) kvm_enable_efer_bits(EFER_NX);

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