github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-07 14:04:54 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

FROMGIT: KVM: arm64: Don't clobber x4 in __do_hyp_init

Browse Source 
arm_smccc_1_1_hvc() only adds write contraints for x0-3 in the inline
assembly for the HVC instruction so make sure those are the only
registers that change when __do_hyp_init is called.

Tested-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210125145415.122439-3-ascull@google.com
(cherry picked from commit e500b805c3
 git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git fixes)
Signed-off-by: Will Deacon <willdeacon@google.com>
Change-Id: I4c3c3b9308bb2ab9ac088fe3d2429a359755298e
Bug: 178098380
Test: atest VirtualizationHostTestCases on an EL2-enabled device
This commit is contained in:
Andrew Scull 2021-01-25 14:54:15 +00:00 committed by Will Deacon
parent 67ba3546fb
commit d8895b745f
1 changed files with 11 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
arch/arm64/kvm/hyp/nvhe/hyp-init.S
View File

@ -47,6 +47,8 @@ __invalid:
b .
/*
* Only uses x0..x3 so as to not clobber callee-saved SMCCC registers.
*
* x0: SMCCC function ID
* x1: struct kvm_nvhe_init_params PA
*/
@ -70,9 +72,9 @@ __do_hyp_init:
eret
1: mov x0, x1
mov x4, lr
bl ___kvm_hyp_init
mov lr, x4
mov x3, lr
bl ___kvm_hyp_init // Clobbers x0..x2
mov lr, x3
/* Hello, World! */
mov x0, #SMCCC_RET_SUCCESS
@ -82,8 +84,8 @@ SYM_CODE_END(__kvm_hyp_init)
/*
* Initialize the hypervisor in EL2.
*
* Only uses x0..x3 so as to not clobber callee-saved SMCCC registers
* and leave x4 for the caller.
* Only uses x0..x2 so as to not clobber callee-saved SMCCC registers
* and leave x3 for the caller.
*
* x0: struct kvm_nvhe_init_params PA
*/
@ -112,9 +114,9 @@ alternative_else_nop_endif
/*
* Set the PS bits in TCR_EL2.
*/
ldr x1, [x0, #NVHE_INIT_TCR_EL2]
tcr_compute_pa_size x1, #TCR_EL2_PS_SHIFT, x2, x3
msr tcr_el2, x1
ldr x0, [x0, #NVHE_INIT_TCR_EL2]
tcr_compute_pa_size x0, #TCR_EL2_PS_SHIFT, x1, x2
msr tcr_el2, x0
isb
@ -193,7 +195,7 @@ SYM_CODE_START_LOCAL(__kvm_hyp_init_cpu)
/* Enable MMU, set vectors and stack. */
mov x0, x28
bl ___kvm_hyp_init // Clobbers x0..x3
bl ___kvm_hyp_init // Clobbers x0..x2
/* Leave idmap. */
mov x0, x29