4.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> commit d222af072380c4470295c07d84ecb15f4937e365 upstream. 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. Fixes: 2c4fb78f78b6 ("KVM: PPC: Book3S HV: Workaround POWER9 DD1.0 bug causing IPB bit loss") Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Paul Mackerras <paulus@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/kvm/book3s_hv_rm_xive.c | 1 - arch/powerpc/kvm/book3s_xive.c | 1 - arch/powerpc/kvm/book3s_xive_template.c | 7 ++++--- 3 files changed, 4 insertions(+), 5 deletions(-) --- a/arch/powerpc/kvm/book3s_hv_rm_xive.c +++ b/arch/powerpc/kvm/book3s_hv_rm_xive.c @@ -38,7 +38,6 @@ static inline void __iomem *get_tima_phy #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 --- a/arch/powerpc/kvm/book3s_xive.c +++ b/arch/powerpc/kvm/book3s_xive.c @@ -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 --- a/arch/powerpc/kvm/book3s_xive_template.c +++ b/arch/powerpc/kvm/book3s_xive_template.c @@ -28,7 +28,8 @@ static void GLUE(X_PFX,ack_pending)(stru * 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_ipol 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_ipol 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; }