iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

KVM: PPC: Book3S HV: Don't access XIVE PIPR register using byte accesses

Browse Source 
The XIVE interrupt controller on POWER9 machines doesn't support byte
accesses to any register in the thread management area other than the
CPPR (current processor priority register).  In particular, when
reading the PIPR (pending interrupt priority register), we need to
do a 32-bit or 64-bit load.

Cc: stable@vger.kernel.org # v4.13
Fixes: 2c4fb78f78 ("KVM: PPC: Book3S HV: Workaround POWER9 DD1.0 bug causing IPB bit loss")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Benjamin Herrenschmidt 2017-09-06 15:20:55 +10:00 committed by Paul Mackerras
parent 5f54c8b2d4
commit d222af0723
3 changed files with 4 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
arch/powerpc/kvm/book3s_hv_rm_xive.c
View File

@ -38,7 +38,6 @@ static inline void __iomem *get_tima_phys(void)
#define __x_tima get_tima_phys()
#define __x_eoi_page(xd) ((void __iomem *)((xd)->eoi_page))
#define __x_trig_page(xd) ((void __iomem *)((xd)->trig_page))
#define __x_readb __raw_rm_readb
#define __x_writeb __raw_rm_writeb
#define __x_readw __raw_rm_readw
#define __x_readq __raw_rm_readq

1
arch/powerpc/kvm/book3s_xive.c
View File

@ -48,7 +48,6 @@
#define __x_tima xive_tima
#define __x_eoi_page(xd) ((void __iomem *)((xd)->eoi_mmio))
#define __x_trig_page(xd) ((void __iomem *)((xd)->trig_mmio))
#define __x_readb __raw_readb
#define __x_writeb __raw_writeb
#define __x_readw __raw_readw
#define __x_readq __raw_readq

7
arch/powerpc/kvm/book3s_xive_template.c
View File

@ -28,7 +28,8 @@ static void GLUE(X_PFX,ack_pending)(struct kvmppc_xive_vcpu *xc)
* bit.
*/
if (cpu_has_feature(CPU_FTR_POWER9_DD1)) {
u8 pipr = __x_readb(__x_tima + TM_QW1_OS + TM_PIPR);
__be64 qw1 = __x_readq(__x_tima + TM_QW1_OS);
u8 pipr = be64_to_cpu(qw1) & 0xff;
if (pipr >= xc->hw_cppr)
return;
}
@ -336,7 +337,6 @@ X_STATIC unsigned long GLUE(X_PFX,h_ipoll)(struct kvm_vcpu *vcpu, unsigned long
struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
u8 pending = xc->pending;
u32 hirq;
u8 pipr;
pr_devel("H_IPOLL(server=%ld)\n", server);
@ -353,7 +353,8 @@ X_STATIC unsigned long GLUE(X_PFX,h_ipoll)(struct kvm_vcpu *vcpu, unsigned long
pending = 0xff;
} else {
/* Grab pending interrupt if any */
pipr = __x_readb(__x_tima + TM_QW1_OS + TM_PIPR);
__be64 qw1 = __x_readq(__x_tima + TM_QW1_OS);
u8 pipr = be64_to_cpu(qw1) & 0xff;
if (pipr < 8)
pending |= 1 << pipr;
}