From: Avi Kivity <avi@redhat.com>
To: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH 10/39] KVM: PPC: Get rid of unnecessary RFI
Date: Sat, 13 Feb 2010 10:01:30 +0200 [thread overview]
Message-ID: <1266048119-14325-11-git-send-email-avi@redhat.com> (raw)
In-Reply-To: <1266048119-14325-1-git-send-email-avi@redhat.com>
From: Alexander Graf <agraf@suse.de>
Using an RFI in IR=1 is dangerous. We need to set two SRRs and then do an RFI
without getting interrupted at all, because every interrupt could potentially
overwrite the SRR values.
Fortunately, we don't need to RFI in at least this particular case of the code,
so we can just replace it with an mtmsr and b.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
arch/powerpc/kvm/book3s_64_interrupts.S | 22 +++++++++++-----------
1 files changed, 11 insertions(+), 11 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_64_interrupts.S b/arch/powerpc/kvm/book3s_64_interrupts.S
index 66e3b11..3c0ba55 100644
--- a/arch/powerpc/kvm/book3s_64_interrupts.S
+++ b/arch/powerpc/kvm/book3s_64_interrupts.S
@@ -221,15 +221,8 @@ no_dcbz32_off:
mflr r5
std r5, VCPU_LR(r7)
- /* XXX convert to safe function call */
-
/* Restore host msr -> SRR1 */
ld r6, VCPU_HOST_MSR(r7)
- mtsrr1 r6
-
- /* Restore host IP -> SRR0 */
- ld r5, VCPU_HOST_RETIP(r7)
- mtsrr0 r5
/*
* For some interrupts, we need to call the real Linux
@@ -246,8 +239,9 @@ no_dcbz32_off:
cmpwi r12, BOOK3S_INTERRUPT_DECREMENTER
beq call_linux_handler
- /* Back to Interruptable Mode! (goto kvm_return_point) */
- RFI
+ /* Back to EE=1 */
+ mtmsr r6
+ b kvm_return_point
call_linux_handler:
@@ -260,10 +254,16 @@ call_linux_handler:
* interrupt handler!
*
* R3 still contains the exit code,
- * R6 VCPU_HOST_RETIP and
- * R7 VCPU_HOST_MSR
+ * R5 VCPU_HOST_RETIP and
+ * R6 VCPU_HOST_MSR
*/
+ /* Restore host IP -> SRR0 */
+ ld r5, VCPU_HOST_RETIP(r7)
+
+ /* XXX Better move to a safe function?
+ * What if we get an HTAB flush in between mtsrr0 and mtsrr1? */
+
mtlr r12
ld r4, VCPU_TRAMPOLINE_LOWMEM(r7)
--
1.6.5.3
next prev parent reply other threads:[~2010-02-13 8:02 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-13 8:01 [PATCH 00/39] KVM updates for the 2.6.34 merge window (batch 2/4) Avi Kivity
2010-02-13 8:01 ` [PATCH 01/39] KVM: PPC: Enable lightweight exits again Avi Kivity
2010-02-13 8:01 ` [PATCH 02/39] KVM: x86: Moving PT_*_LEVEL to mmu.h Avi Kivity
2010-02-13 8:01 ` [PATCH 03/39] KVM: x86: Rename gb_page_enable() to get_lpage_level() in kvm_x86_ops Avi Kivity
2010-02-13 8:01 ` [PATCH 04/39] KVM: VMX: Enable EPT 1GB page support Avi Kivity
2010-02-13 8:01 ` [PATCH 05/39] KVM: Fix the explanation of write_emulated Avi Kivity
2010-02-13 8:01 ` [PATCH 06/39] KVM: PPC: Use accessor functions for GPR access Avi Kivity
2010-02-13 8:01 ` [PATCH 07/39] KVM: PPC: Add helpers for CR, XER Avi Kivity
2010-02-13 8:01 ` [PATCH 08/39] KVM: PPC: Use PACA backed shadow vcpu Avi Kivity
2010-02-13 8:01 ` [PATCH 09/39] KVM: PPC: Implement 'skip instruction' mode Avi Kivity
2010-02-13 8:01 ` Avi Kivity [this message]
2010-02-13 8:01 ` [PATCH 11/39] KVM: PPC: Call SLB patching code in interrupt safe manner Avi Kivity
2010-02-13 8:01 ` [PATCH 12/39] KVM: PPC: Emulate trap SRR1 flags properly Avi Kivity
2010-02-13 8:01 ` [PATCH 13/39] KVM: PPC: Fix HID5 setting code Avi Kivity
2010-02-13 8:01 ` [PATCH 14/39] KVM: PPC: Pass program interrupt flags to the guest Avi Kivity
2010-02-13 8:01 ` [PATCH 15/39] KVM: PPC: Pass through program interrupts Avi Kivity
2010-02-13 8:01 ` [PATCH 16/39] KVM: PPC: Make large pages work Avi Kivity
2010-02-13 8:01 ` [PATCH 17/39] KVM: VMX: trace clts and lmsw instructions as cr accesses Avi Kivity
2010-02-13 8:01 ` [PATCH 18/39] KVM: Replace read accesses of vcpu->arch.cr0 by an accessor Avi Kivity
2010-02-13 8:01 ` [PATCH 19/39] KVM: VMX: Allow the guest to own some cr0 bits Avi Kivity
2010-02-13 8:01 ` [PATCH 20/39] KVM: Lazify fpu activation and deactivation Avi Kivity
2010-02-13 8:01 ` [PATCH 21/39] KVM: VMX: Give the guest ownership of cr0.ts when the fpu is active Avi Kivity
2010-02-13 8:01 ` [PATCH 22/39] KVM: Set cr0.et when the guest writes cr0 Avi Kivity
2010-02-13 8:01 ` [PATCH 23/39] KVM: SVM: Fix SVM_CR0_SELECTIVE_MASK Avi Kivity
2010-02-13 8:01 ` [PATCH 24/39] KVM: SVM: Initialize fpu_active in init_vmcb() Avi Kivity
2010-02-13 8:01 ` [PATCH 25/39] KVM: SVM: Restore unconditional cr0 intercept under npt Avi Kivity
2010-02-13 8:01 ` [PATCH 26/39] KVM: SVM: Selective cr0 intercept Avi Kivity
2010-02-13 8:01 ` [PATCH 27/39] KVM: SVM: Lazy fpu with npt Avi Kivity
2010-02-13 8:01 ` [PATCH 28/39] KVM: ia64: remove redundant kvm_get_exit_data() NULL tests Avi Kivity
2010-02-13 8:01 ` [PATCH 29/39] KVM: PPC: Export __giveup_vsx Avi Kivity
2010-02-13 8:01 ` [PATCH 30/39] KVM: PPC: Add helper functions to call real mode loaders Avi Kivity
2010-02-13 8:01 ` [PATCH 31/39] KVM: PPC: Add support for FPU/Altivec/VSX Avi Kivity
2010-02-13 8:01 ` [PATCH 32/39] KVM: PPC: Fix initial GPR settings Avi Kivity
2010-02-13 8:01 ` [PATCH 33/39] KVM: PPC: Keep SRR1 flags around in shadow_msr Avi Kivity
2010-02-13 8:01 ` [PATCH 34/39] KVM: PPC: Move Shadow MSR calculation to function Avi Kivity
2010-02-13 8:01 ` [PATCH 35/39] KVM: Add HYPER-V header file Avi Kivity
2010-02-13 8:01 ` [PATCH 36/39] KVM: Implement bare minimum of HYPER-V MSRs Avi Kivity
2010-02-13 8:01 ` [PATCH 37/39] KVM: Add HYPER-V apic access MSRs Avi Kivity
2010-02-13 8:01 ` [PATCH 38/39] KVM: Implement NotifyLongSpinWait HYPER-V hypercall Avi Kivity
2010-02-13 8:01 ` [PATCH 39/39] KVM: rename is_writeble_pte() to is_writable_pte() Avi Kivity
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1266048119-14325-11-git-send-email-avi@redhat.com \
--to=avi@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome