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@vger.kernel.org.
Possible dependencies:
f7ef280132f9 ("KVM: SVM: adjust register allocation for __svm_vcpu_run()") 16fdc1de169e ("KVM: SVM: replace regs argument of __svm_vcpu_run() with vcpu_svm") debc5a1ec0d1 ("KVM: x86: use a separate asm-offsets.c file") bb06650634d3 ("KVM: VMX: Convert launched argument to flags") 8bd200d23ec4 ("KVM: VMX: Flatten __vmx_vcpu_run()") 527a534c7326 ("x86/tdx: Provide common base for SEAMCALL and TDCALL C wrappers") 59bd54a84d15 ("x86/tdx: Detect running as a TDX guest in early boot") 6198311093da ("x86/cc: Move arch/x86/{kernel/cc_platform.c => coco/core.c}") f94909ceb1ed ("x86: Prepare asm files for straight-line-speculation") 22da5a07c75e ("x86/lib/atomic64_386_32: Rename things") 1367afaa2ee9 ("x86/entry: Use the correct fence macro after swapgs in kernel CR3") c07e45553da1 ("x86/entry: Add a fence for kernel entry SWAPGS in paranoid_entry()") 6e5772c8d9cf ("Merge tag 'x86_cc_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f7ef280132f9bf6f82acf5aa5c3c837206eef501 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini pbonzini@redhat.com Date: Fri, 28 Oct 2022 17:30:07 -0400 Subject: [PATCH] KVM: SVM: adjust register allocation for __svm_vcpu_run()
32-bit ABI uses RAX/RCX/RDX as its argument registers, so they are in the way of instructions that hardcode their operands such as RDMSR/WRMSR or VMLOAD/VMRUN/VMSAVE.
In preparation for moving vmload/vmsave to __svm_vcpu_run(), keep the pointer to the struct vcpu_svm in %rdi. In particular, it is now possible to load svm->vmcb01.pa in %rax without clobbering the struct vcpu_svm pointer.
No functional change intended.
Cc: stable@vger.kernel.org Fixes: a149180fbcf3 ("x86: Add magic AMD return-thunk") Reviewed-by: Sean Christopherson seanjc@google.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com
diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S index f0ff41103e4c..531510ab6072 100644 --- a/arch/x86/kvm/svm/vmenter.S +++ b/arch/x86/kvm/svm/vmenter.S @@ -54,29 +54,29 @@ SYM_FUNC_START(__svm_vcpu_run) /* Save @vmcb. */ push %_ASM_ARG1
- /* Move @svm to RAX. */ - mov %_ASM_ARG2, %_ASM_AX + /* Move @svm to RDI. */ + mov %_ASM_ARG2, %_ASM_DI + + /* "POP" @vmcb to RAX. */ + pop %_ASM_AX
/* Load guest registers. */ - mov VCPU_RCX(%_ASM_AX), %_ASM_CX - mov VCPU_RDX(%_ASM_AX), %_ASM_DX - mov VCPU_RBX(%_ASM_AX), %_ASM_BX - mov VCPU_RBP(%_ASM_AX), %_ASM_BP - mov VCPU_RSI(%_ASM_AX), %_ASM_SI - mov VCPU_RDI(%_ASM_AX), %_ASM_DI + mov VCPU_RCX(%_ASM_DI), %_ASM_CX + mov VCPU_RDX(%_ASM_DI), %_ASM_DX + mov VCPU_RBX(%_ASM_DI), %_ASM_BX + mov VCPU_RBP(%_ASM_DI), %_ASM_BP + mov VCPU_RSI(%_ASM_DI), %_ASM_SI #ifdef CONFIG_X86_64 - mov VCPU_R8 (%_ASM_AX), %r8 - mov VCPU_R9 (%_ASM_AX), %r9 - mov VCPU_R10(%_ASM_AX), %r10 - mov VCPU_R11(%_ASM_AX), %r11 - mov VCPU_R12(%_ASM_AX), %r12 - mov VCPU_R13(%_ASM_AX), %r13 - mov VCPU_R14(%_ASM_AX), %r14 - mov VCPU_R15(%_ASM_AX), %r15 + mov VCPU_R8 (%_ASM_DI), %r8 + mov VCPU_R9 (%_ASM_DI), %r9 + mov VCPU_R10(%_ASM_DI), %r10 + mov VCPU_R11(%_ASM_DI), %r11 + mov VCPU_R12(%_ASM_DI), %r12 + mov VCPU_R13(%_ASM_DI), %r13 + mov VCPU_R14(%_ASM_DI), %r14 + mov VCPU_R15(%_ASM_DI), %r15 #endif - - /* "POP" @vmcb to RAX. */ - pop %_ASM_AX + mov VCPU_RDI(%_ASM_DI), %_ASM_DI
/* Enter guest mode */ sti