diff options
| author | Andrew Scull <ascull@google.com> | 2020-07-06 10:52:59 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-07-16 08:16:43 +0200 |
| commit | b956ec9afc2ee50986f3804a80fddf8755480f54 (patch) | |
| tree | 451268a3a831bf248950f6fd4c8f9eeb43f85003 /arch/arm64/kvm | |
| parent | a20aa35b839aaf55247f85937508ba1b94cf1733 (diff) | |
KVM: arm64: Stop clobbering x0 for HVC_SOFT_RESTART
commit b9e10d4a6c9f5cbe6369ce2c17ebc67d2e5a4be5 upstream.
HVC_SOFT_RESTART is given values for x0-2 that it should installed
before exiting to the new address so should not set x0 to stub HVC
success or failure code.
Fixes: af42f20480bf1 ("arm64: hyp-stub: Zero x0 on successful stub handling")
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200706095259.1338221-1-ascull@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm64/kvm')
| -rw-r--r-- | arch/arm64/kvm/hyp-init.S | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S index 160be2b4696d..dc41b505507d 100644 --- a/arch/arm64/kvm/hyp-init.S +++ b/arch/arm64/kvm/hyp-init.S @@ -136,11 +136,15 @@ ENTRY(__kvm_handle_stub_hvc) 1: cmp x0, #HVC_RESET_VECTORS b.ne 1f -reset: + /* - * Reset kvm back to the hyp stub. Do not clobber x0-x4 in - * case we coming via HVC_SOFT_RESTART. + * Set the HVC_RESET_VECTORS return code before entering the common + * path so that we do not clobber x0-x2 in case we are coming via + * HVC_SOFT_RESTART. */ + mov x0, xzr +reset: + /* Reset kvm back to the hyp stub. */ mrs x5, sctlr_el2 ldr x6, =SCTLR_ELx_FLAGS bic x5, x5, x6 // Clear SCTL_M and etc @@ -151,7 +155,6 @@ reset: /* Install stub vectors */ adr_l x5, __hyp_stub_vectors msr vbar_el2, x5 - mov x0, xzr eret 1: /* Bad stub call */ |