| Message ID | 1509563697-6359-4-git-send-email-gengdongjiu@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Dongjiu,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on arm64/for-next/core]
[also build test ERROR on v4.14-rc7 next-20171103]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Dongjiu-Geng/arm64-add-a-macro-for-SError-synchronization/20171104-224216
base: https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-next/core
config: arm64-allmodconfig (attached as .config)
compiler: aarch64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=arm64
All errors (new ones prefixed by >>):
arch/arm64/kvm/hyp/entry.S: Assembler messages:
>> arch/arm64/kvm/hyp/entry.S:88: Error: selected processor does not support `esb'
--
arch/arm64/kvm/hyp/hyp-entry.S: Assembler messages:
>> arch/arm64/kvm/hyp/hyp-entry.S:57: Error: selected processor does not support `esb'
vim +88 arch/arm64/kvm/hyp/entry.S
51
52 /*
53 * u64 __guest_enter(struct kvm_vcpu *vcpu,
54 * struct kvm_cpu_context *host_ctxt);
55 */
56 ENTRY(__guest_enter)
57 // x0: vcpu
58 // x1: host context
59 // x2-x17: clobbered by macros
60 // x18: guest context
61
62 // Store the host regs
63 save_callee_saved_regs x1
64
65 // Store the host_ctxt for use at exit time
66 str x1, [sp, #-16]!
67
68 add x18, x0, #VCPU_CONTEXT
69
70 // Restore guest regs x0-x17
71 ldp x0, x1, [x18, #CPU_XREG_OFFSET(0)]
72 ldp x2, x3, [x18, #CPU_XREG_OFFSET(2)]
73 ldp x4, x5, [x18, #CPU_XREG_OFFSET(4)]
74 ldp x6, x7, [x18, #CPU_XREG_OFFSET(6)]
75 ldp x8, x9, [x18, #CPU_XREG_OFFSET(8)]
76 ldp x10, x11, [x18, #CPU_XREG_OFFSET(10)]
77 ldp x12, x13, [x18, #CPU_XREG_OFFSET(12)]
78 ldp x14, x15, [x18, #CPU_XREG_OFFSET(14)]
79 ldp x16, x17, [x18, #CPU_XREG_OFFSET(16)]
80
81 // Restore guest regs x19-x29, lr
82 restore_callee_saved_regs x18
83
84 // Restore guest reg x18
85 ldr x18, [x18, #CPU_XREG_OFFSET(18)]
86
87 // synchronize host pending asynchronous error
> 88 error_synchronize
89 // Do not touch any register after this!
90 eret
91 ENDPROC(__guest_enter)
92
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S index 96caa53..fce6806 100644 --- a/arch/arm64/kvm/hyp/entry.S +++ b/arch/arm64/kvm/hyp/entry.S @@ -84,6 +84,8 @@ ENTRY(__guest_enter) // Restore guest reg x18 ldr x18, [x18, #CPU_XREG_OFFSET(18)] + // synchronize host pending asynchronous error + error_synchronize // Do not touch any register after this! eret ENDPROC(__guest_enter) diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S index 5170ce1..ac85029 100644 --- a/arch/arm64/kvm/hyp/hyp-entry.S +++ b/arch/arm64/kvm/hyp/hyp-entry.S @@ -54,6 +54,7 @@ ENTRY(__vhe_hyp_call) ENDPROC(__vhe_hyp_call) el1_sync: // Guest trapped into EL2 + error_synchronize stp x0, x1, [sp, #-16]! alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
Some hardware platform can support RAS Extension instead of support IESB, so software need to insert Synchronization Barrier operations at exception handler entry and exit. In the __guest_exit(), it added a ESB instruction, but can not cover the path which is not guest exit. For example, if EL1 host call HVC instruction enter to hypervisor, it will not call __guest_exit(). In the kvm_arm_vhe_guest_enter(), it synchronised any host RAS errors for VHE mode, but it can not handle the non-VHE mode. For example, if EL1 host is pending a SError, the error can be propagated to guest without error synchronization operation. Only add the ESB in the important exception handler path to reduce the impact on performance. Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com> --- arch/arm64/kvm/hyp/entry.S | 2 ++ arch/arm64/kvm/hyp/hyp-entry.S | 1 + 2 files changed, 3 insertions(+)