Switching topics, dropped everyone else except the list.
On Fri, Dec 20, 2024, Sean Christopherson wrote:
> arch/x86/kvm/x86.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 4320647bd78a..9d5cece9260b 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -1186,7 +1186,7 @@ void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu)
> vcpu->arch.pkru != vcpu->arch.host_pkru &&
> ((vcpu->arch.xcr0 & XFEATURE_MASK_PKRU) ||
> kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE)))
> - write_pkru(vcpu->arch.pkru);
> + wrpkru(vcpu->arch.pkru);
> }
> EXPORT_SYMBOL_GPL(kvm_load_guest_xsave_state);
>
> @@ -1200,7 +1200,7 @@ void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu)
> kvm_is_cr4_bit_set(vcpu, X86_CR4_PKE))) {
> vcpu->arch.pkru = rdpkru();
> if (vcpu->arch.pkru != vcpu->arch.host_pkru)
> - write_pkru(vcpu->arch.host_pkru);
> + wrpkru(vcpu->arch.host_pkru);
> }
>
> if (kvm_is_cr4_bit_set(vcpu, X86_CR4_OSXSAVE)) {
>
> base-commit: 13e98294d7cec978e31138d16824f50556a62d17
> --
I tried to test this by running the mm/protection_keys selftest in a VM, but it
gives what are effectively false passes on x86-64 due to the selftest picking up
the generic syscall numbers, e.g. 289 for SYS_pkey_alloc, instead of the x86-64
numbers.
I was able to get the test to run by hacking tools/testing/selftests/mm/pkey-x86.h
to shove in the right numbers, but I can't imagine that's the intended behavior.
If I omit the #undefs from pkey-x86.h, it shows that the test is grabbing the
definitions from the generic usr/include/asm-generic/unistd.h header.
Am I doing something stupid?
Regardless of whether this is PEBKAC or working as intended, on x86, the test
should ideally assert that "ospke" support in /proc/cpuinfo is consistent with
the result of sys_pkey_alloc(), e.g. so that an failure to allocate a pkey on a
system that work is reported as an error, not a pass.
--
diff --git a/tools/testing/selftests/mm/pkey-x86.h b/tools/testing/selftests/mm/pkey-x86.h
index ac91777c8917..ccc3552e6b77 100644
--- a/tools/testing/selftests/mm/pkey-x86.h
+++ b/tools/testing/selftests/mm/pkey-x86.h
@@ -3,6 +3,10 @@
#ifndef _PKEYS_X86_H
#define _PKEYS_X86_H
+#define __NR_pkey_mprotect 329
+#define __NR_pkey_alloc 330
+#define __NR_pkey_free 331
+
#ifdef __i386__
#define REG_IP_IDX REG_EIP
--
Yields:
$ ARCH=x86_64 make protection_keys_64
gcc -Wall -I /home/sean/go/src/kernel.org/linux/tools/testing/selftests/../../.. -isystem /home/sean/go/src/kernel.org/linux/tools/testing/selftests/../../../usr/include -isystem /home/sean/go/src/kernel.org/linux/tools/testing/selftests/../../../tools/include/uapi -no-pie -D_GNU_SOURCE= -m64 -mxsave protection_keys.c vm_util.c thp_settings.c -lrt -lpthread -lm -lrt -ldl -o /home/sean/go/src/kernel.org/linux/tools/testing/selftests/mm/protection_keys_64
In file included from pkey-helpers.h:102:0,
from protection_keys.c:49:
pkey-x86.h:6:0: warning: "__NR_pkey_mprotect" redefined
#define __NR_pkey_mprotect 329
In file included from protection_keys.c:45:0:
/home/sean/go/src/kernel.org/linux/usr/include/asm-generic/unistd.h:693:0: note: this is the location of the previous definition
#define __NR_pkey_mprotect 288
In file included from pkey-helpers.h:102:0,
from protection_keys.c:49:
pkey-x86.h:7:0: warning: "__NR_pkey_alloc" redefined
#define __NR_pkey_alloc 330
In file included from protection_keys.c:45:0:
/home/sean/go/src/kernel.org/linux/usr/include/asm-generic/unistd.h:695:0: note: this is the location of the previous definition
#define __NR_pkey_alloc 289
In file included from pkey-helpers.h:102:0,
from protection_keys.c:49:
pkey-x86.h:8:0: warning: "__NR_pkey_free" redefined
#define __NR_pkey_free 331
In file included from protection_keys.c:45:0:
/home/sean/go/src/kernel.org/linux/usr/include/asm-generic/unistd.h:697:0: note: this is the location of the previous definition
#define __NR_pkey_free 290
