On Fri, Nov 03, 2017 at 03:38:03PM +1100, Nicholas Piggin wrote:
> If the host takes a system reset interrupt while a guest is running,
> the CPU must exit the guest before processing the host exception
> handler.
>
> After this patch, taking a sysrq+x with a CPU running in a guest
> gives a trace like this:
>
> cpu 0x27: Vector: 100 (System Reset) at [c000000fdf5776f0]
> pc: c008000010158b80: kvmppc_run_core+0x16b8/0x1ad0 [kvm_hv]
> lr: c008000010158b80: kvmppc_run_core+0x16b8/0x1ad0 [kvm_hv]
> sp: c000000fdf577850
> msr: 9000000002803033
> current = 0xc000000fdf4b1e00
> paca = 0xc00000000fd4d680 softe: 3 irq_happened: 0x01
> pid = 6608, comm = qemu-system-ppc
> Linux version 4.14.0-rc7-01489-g47e1893a404a-dirty #26 SMP
> [c000000fdf577a00] c008000010159dd4 kvmppc_vcpu_run_hv+0x3dc/0x12d0 [kvm_hv]
> [c000000fdf577b30] c0080000100a537c kvmppc_vcpu_run+0x44/0x60 [kvm]
> [c000000fdf577b60] c0080000100a1ae0 kvm_arch_vcpu_ioctl_run+0x118/0x310 [kvm]
> [c000000fdf577c00] c008000010093e98 kvm_vcpu_ioctl+0x530/0x7c0 [kvm]
> [c000000fdf577d50] c000000000357bf8 do_vfs_ioctl+0xd8/0x8c0
> [c000000fdf577df0] c000000000358448 SyS_ioctl+0x68/0x100
> [c000000fdf577e30] c00000000000b220 system_call+0x58/0x6c
> --- Exception: c01 (System Call) at 00007fff76868df0
> SP (7fff7069baf0) is in userspace
>
> Fixes: e36d0a2ed5 ("powerpc/powernv: Implement NMI IPI with OPAL_SIGNAL_SYSTEM_RESET")
> Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
Looks good, except that you don't need the last hunk (the change to
book3s_hv_rmhandlers.S) as far as I can see:
> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> index 68bf0f14a962..74958ad5efb9 100644
> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
> @@ -1427,6 +1427,10 @@ guest_exit_cont: /* r9 = vcpu, r12 = trap, r13 = paca */
> /* don't overwrite fault_dar/fault_dsisr if HDSI */
> cmpwi r12,BOOK3S_INTERRUPT_H_DATA_STORAGE
> beq mc_cont
> +
> + cmpwi r12, BOOK3S_INTERRUPT_SYSTEM_RESET
> + beq mc_cont
> +
> std r6, VCPU_FAULT_DAR(r9)
> stw r7, VCPU_FAULT_DSISR(r9)
>
> --
> 2.15.0
Paul.
--
To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
