On 10/02/21 04:17, Ricardo Koller wrote:
Building the KVM selftests with LLVM's integrated assembler fails with: $ CFLAGS=-fintegrated-as make -C tools/testing/selftests/kvm CC=clang lib/x86_64/svm.c:77:16: error: too few operands for instruction asm volatile ("vmsave\n\t" : : "a" (vmcb_gpa) : "memory"); ^ <inline asm>:1:2: note: instantiated into assembly here vmsave ^ lib/x86_64/svm.c:134:3: error: too few operands for instruction "vmload\n\t" ^ <inline asm>:1:2: note: instantiated into assembly here vmload ^ This is because LLVM IAS does not currently support calling vmsave, vmload, or vmload without an explicit %rax operand. Add an explicit operand to vmsave, vmload, and vmrum in svm.c. Fixing this was suggested by Sean Christopherson. Tested: building without this error in clang 11. The following patch (not queued yet) needs to be applied to solve the other remaining error: "selftests: kvm: remove reassignment of non-absolute variables". Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx> Link: https://lore.kernel.org/kvm/X+Df2oQczVBmwEzi@xxxxxxxxxx/ Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx> Signed-off-by: Ricardo Koller <ricarkol@xxxxxxxxxx> --- tools/testing/selftests/kvm/lib/x86_64/svm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/kvm/lib/x86_64/svm.c b/tools/testing/selftests/kvm/lib/x86_64/svm.c index 3a5c72ed2b79..827fe6028dd4 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/svm.c +++ b/tools/testing/selftests/kvm/lib/x86_64/svm.c @@ -74,7 +74,7 @@ void generic_svm_setup(struct svm_test_data *svm, void *guest_rip, void *guest_r wrmsr(MSR_VM_HSAVE_PA, svm->save_area_gpa);memset(vmcb, 0, sizeof(*vmcb));- asm volatile ("vmsave\n\t" : : "a" (vmcb_gpa) : "memory"); + asm volatile ("vmsave %0\n\t" : : "a" (vmcb_gpa) : "memory"); vmcb_set_seg(&save->es, get_es(), 0, -1U, data_seg_attr); vmcb_set_seg(&save->cs, get_cs(), 0, -1U, code_seg_attr); vmcb_set_seg(&save->ss, get_ss(), 0, -1U, data_seg_attr); @@ -131,19 +131,19 @@ void generic_svm_setup(struct svm_test_data *svm, void *guest_rip, void *guest_r void run_guest(struct vmcb *vmcb, uint64_t vmcb_gpa) { asm volatile ( - "vmload\n\t" + "vmload %[vmcb_gpa]\n\t" "mov rflags, %%r15\n\t" // rflags "mov %%r15, 0x170(%[vmcb])\n\t" "mov guest_regs, %%r15\n\t" // rax "mov %%r15, 0x1f8(%[vmcb])\n\t" LOAD_GPR_C - "vmrun\n\t" + "vmrun %[vmcb_gpa]\n\t" SAVE_GPR_C "mov 0x170(%[vmcb]), %%r15\n\t" // rflags "mov %%r15, rflags\n\t" "mov 0x1f8(%[vmcb]), %%r15\n\t" // rax "mov %%r15, guest_regs\n\t" - "vmsave\n\t" + "vmsave %[vmcb_gpa]\n\t" : : [vmcb] "r" (vmcb), [vmcb_gpa] "a" (vmcb_gpa) : "r15", "memory"); }
Queued, thanks. Paolo
