pve-kernel-lowlatency-qoup/patches/kernel/0007-KVM-x86-emulator-update-the-emulation-mode-after-rsm.patch
Fabian Grünbichler 826eb0ff89 build: re-enable BTF
but allow discarding BTF information when loading modules, so that upgrades
which are otherwise ABI compatible still work. this allows using BTF
information when matching and available, while degrading gracefully if the
currently running kernel is not identical to the one that module was built for.

in case of a mismatch, the kernel will log a warning when loading the module,
for example:

Jan 30 13:57:58 test kernel: BPF:          type_id=184 bits_offset=4096
Jan 30 13:57:58 test kernel: BPF:
Jan 30 13:57:58 test kernel: BPF: Invalid name
Jan 30 13:57:58 test kernel: BPF:
Jan 30 13:57:58 test kernel: failed to validate module [bonding] BTF: -22

Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
2023-01-31 17:44:18 +01:00

39 lines
1.3 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Wed, 3 Aug 2022 18:50:02 +0300
Subject: [PATCH] KVM: x86: emulator: update the emulation mode after rsm
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
This ensures that RIP will be correctly written back,
because the RSM instruction can switch the CPU mode from
32 bit (or less) to 64 bit.
This fixes a guest crash in case the #SMI is received
while the guest runs a code from an address > 32 bit.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
---
arch/x86/kvm/emulate.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 4a43261d25a2..4f7f5117ec7a 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2654,6 +2654,11 @@ static int em_rsm(struct x86_emulate_ctxt *ctxt)
if (ret != X86EMUL_CONTINUE)
goto emulate_shutdown;
+
+ ret = emulator_recalc_and_set_mode(ctxt);
+ if (ret != X86EMUL_CONTINUE)
+ goto emulate_shutdown;
+
/*
* Note, the ctxt->ops callbacks are responsible for handling side
* effects when writing MSRs and CRs, e.g. MMU context resets, CPUID