redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

KVM: PPC: Save/Restore CR over vcpu_run 

On PPC, CR2-CR4 are nonvolatile, thus have to be saved across function calls.
We didn't respect that for any architecture until Paul spotted it in his
patch for Book3S-HV. This patch saves/restores CR for all KVM capable PPC hosts.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
hifive-unleashed-5.1
Alexander Graf 2012-03-05 16:00:28 +01:00 committed by Paul Mackerras
parent a5ddea0e78
commit e1f8acf838
2 changed files with 13 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
arch/powerpc/kvm/book3s_interrupts.S
View File

@ -84,6 +84,10 @@ kvm_start_entry:
/* Save non-volatile registers (r14 - r31) */
SAVE_NVGPRS(r1)
/* Save CR */
mfcr r14
stw r14, _CCR(r1)
/* Save LR */
PPC_STL r0, _LINK(r1)
@ -165,6 +169,9 @@ kvm_exit_loop:
PPC_LL r4, _LINK(r1)
mtlr r4
lwz r14, _CCR(r1)
mtcr r14
/* Restore non-volatile host registers (r14 - r31) */
REST_NVGPRS(r1)

7
arch/powerpc/kvm/booke_interrupts.S
View File

@ -34,7 +34,8 @@
/* r2 is special: it holds 'current', and it made nonvolatile in the
* kernel with the -ffixed-r2 gcc option. */
#define HOST_R2 12
#define HOST_NV_GPRS 16
#define HOST_CR 16
#define HOST_NV_GPRS 20
#define HOST_NV_GPR(n) (HOST_NV_GPRS + ((n - 14) * 4))
#define HOST_MIN_STACK_SIZE (HOST_NV_GPR(31) + 4)
#define HOST_STACK_SIZE (((HOST_MIN_STACK_SIZE + 15) / 16) * 16) /* Align. */
@ -296,8 +297,10 @@ heavyweight_exit:
/* Return to kvm_vcpu_run(). */
lwz r4, HOST_STACK_LR(r1)
lwz r5, HOST_CR(r1)
addi r1, r1, HOST_STACK_SIZE
mtlr r4
mtcr r5
/* r3 still contains the return code from kvmppc_handle_exit(). */
blr
@ -314,6 +317,8 @@ _GLOBAL(__kvmppc_vcpu_run)
stw r3, HOST_RUN(r1)
mflr r3
stw r3, HOST_STACK_LR(r1)
mfcr r5
stw r5, HOST_CR(r1)
/* Save host non-volatile register state to stack. */
stw r14, HOST_NV_GPR(r14)(r1)