On 2020/5/26 13:59, Paul Mackerras wrote:
On Mon, Apr 27, 2020 at 12:35:12PM +0800, Tianjia Zhang wrote:
In the current kvm version, 'kvm_run' has been included in the 'kvm_vcpu'
structure. For historical reasons, many kvm-related function parameters
retain the 'kvm_run' and 'kvm_vcpu' parameters at the same time. This
patch does a unified cleanup of these remaining redundant parameters.
Some of these changes don't look completely correct to me, see below.
If you're expecting these patches to go through my tree, I can fix up
the patch and commit it (with you as author), noting the changes I
made in the commit message. Do you want me to do that?
I am very glad for you to do so, although I have submitted a new version
of patch, I still prefer you to fix up and commit it.
Thanks and best,
Tianjia
diff --git a/arch/powerpc/kvm/book3s_interrupts.S b/arch/powerpc/kvm/book3s_interrupts.S
index f7ad99d972ce..0eff749d8027 100644
--- a/arch/powerpc/kvm/book3s_interrupts.S
+++ b/arch/powerpc/kvm/book3s_interrupts.S
@@ -55,8 +55,7 @@
****************************************************************************/
/* Registers:
- * r3: kvm_run pointer
- * r4: vcpu pointer
+ * r3: vcpu pointer
*/
_GLOBAL(__kvmppc_vcpu_run)
@@ -68,8 +67,8 @@ kvm_start_entry:
/* Save host state to the stack */
PPC_STLU r1, -SWITCH_FRAME_SIZE(r1)
- /* Save r3 (kvm_run) and r4 (vcpu) */
- SAVE_2GPRS(3, r1)
+ /* Save r3 (vcpu) */
+ SAVE_GPR(3, r1)
/* Save non-volatile registers (r14 - r31) */
SAVE_NVGPRS(r1)
@@ -82,11 +81,11 @@ kvm_start_entry:
PPC_STL r0, _LINK(r1)
/* Load non-volatile guest state from the vcpu */
- VCPU_LOAD_NVGPRS(r4)
+ VCPU_LOAD_NVGPRS(r3)
kvm_start_lightweight:
/* Copy registers into shadow vcpu so we can access them in real mode */
- mr r3, r4
+ mr r4, r3
This mr doesn't seem necessary.
bl FUNC(kvmppc_copy_to_svcpu)
nop
REST_GPR(4, r1)
This should be loading r4 from GPR3(r1), not GPR4(r1) - which is what
REST_GPR(4, r1) will do.
Then, in the file but not in the patch context, there is this line:
PPC_LL r3, GPR4(r1) /* vcpu pointer */
where once again GPR4 needs to be GPR3.
@@ -191,10 +190,10 @@ after_sprg3_load:
PPC_STL r31, VCPU_GPR(R31)(r7)
/* Pass the exit number as 3rd argument to kvmppc_handle_exit */
The comment should be modified to say "2nd" instead of "3rd",
otherwise it is confusing.
The rest of the patch looks OK.
Paul.
