shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-07 19:30:30 +09:00
Code Issues Packages Projects Releases Wiki Activity

UPSTREAM: KVM: arm64: Generally disallow SMC64 for AArch32 guests

Browse Source 
The only valid calling SMC calling convention from an AArch32 state is
SMC32. Disallow any PSCI function that sets the SMC64 function ID bit
when called from AArch32 rather than comparing against known SMC64 PSCI
functions.

Note that without this change KVM advertises the SMC64 flavor of
SYSTEM_RESET2 to AArch32 guests.

Bug: 254441685
Fixes: d43583b890 ("KVM: arm64: Expose PSCI SYSTEM_RESET2 call to the guest")
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Reiji Watanabe <reijiw@google.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220322183538.2757758-2-oupton@google.com
(cherry picked from commit 2da0aebc74)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I9cf0a30d93c5627bf0f4042e98bb1640c61ea156
This commit is contained in:
Oliver Upton
2022-03-22 18:35:36 +00:00
committed by Treehugger Robot
parent 1eed68cdc9
commit c6408580e1
1 changed files with 5 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
arch/arm64/kvm/psci.c
View File

@@ -188,15 +188,11 @@ static void kvm_psci_system_reset2(struct kvm_vcpu *vcpu)
static unsigned long kvm_psci_check_allowed_function(struct kvm_vcpu *vcpu, u32 fn)
{
switch(fn) {
case PSCI_0_2_FN64_CPU_SUSPEND:
case PSCI_0_2_FN64_CPU_ON:
case PSCI_0_2_FN64_AFFINITY_INFO:
/* Disallow these functions for 32bit guests */
if (vcpu_mode_is_32bit(vcpu))
return PSCI_RET_NOT_SUPPORTED;
break;
}
/*
* Prevent 32 bit guests from calling 64 bit PSCI functions.
*/
if ((fn & PSCI_0_2_64BIT) && vcpu_mode_is_32bit(vcpu))
return PSCI_RET_NOT_SUPPORTED;
return 0;
}