From 49b99e1e0dedbd6cc93b2d2776b60fb7151ff3d7 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Fri, 17 May 2013 14:41:35 +0200 Subject: s390/kvm: Provide a way to prevent reentering SIE Lets provide functions to prevent KVM from reentering SIE and to kick cpus out of SIE. We cannot use the common kvm_vcpu_kick code, since we need to kick out guests in places that hold architecture specific locks (e.g. pgste lock) which might be necessary on the other cpus - so no waiting possible. So lets provide a bit in a private field of the sie control block that acts as a gate keeper, after we claimed we are in SIE. Please note that we do not reuse prog0c, since we want to access that bit without atomic ops. Signed-off-by: Christian Borntraeger Acked-by: Martin Schwidefsky Signed-off-by: Gleb Natapov --- arch/s390/include/asm/kvm_host.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'arch/s390/include') diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index 962b92e6cf00..9a809f935580 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -71,7 +71,10 @@ struct kvm_s390_sie_block { __u8 reserved08[4]; /* 0x0008 */ #define PROG_IN_SIE (1<<0) __u32 prog0c; /* 0x000c */ - __u8 reserved10[24]; /* 0x0010 */ + __u8 reserved10[16]; /* 0x0010 */ +#define PROG_BLOCK_SIE 0x00000001 + atomic_t prog20; /* 0x0020 */ + __u8 reserved24[4]; /* 0x0024 */ __u64 cputm; /* 0x0028 */ __u64 ckc; /* 0x0030 */ __u64 epoch; /* 0x0038 */ -- cgit v1.2.2