From d6776bba44d9752f6cdf640046070e71ee4bba7b Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 22 Apr 2016 14:57:48 +1000 Subject: [PATCH 1/3] cxl: Keep IRQ mappings on context teardown Keep IRQ mappings on context teardown. This won't leak IRQs as if we allocate the mapping again, the generic code will give the same mapping used last time. Doing this works around a race in the generic code. Masking the interrupt introduces a race which can crash the kernel or result in IRQ that is never EOIed. The lost of EOI results in all subsequent mappings to the same HW IRQ never receiving an interrupt. We've seen this race with cxl test cases which are doing heavy context startup and teardown at the same time as heavy interrupt load. A fix to the generic code is being investigated also. Signed-off-by: Michael Neuling Cc: stable@vger.kernel.org # 3.8 Tested-by: Andrew Donnellan Acked-by: Ian Munsie Tested-by: Vaibhav Jain Signed-off-by: Michael Ellerman --- drivers/misc/cxl/irq.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/misc/cxl/irq.c b/drivers/misc/cxl/irq.c index be646dc41a2c..8def4553acba 100644 --- a/drivers/misc/cxl/irq.c +++ b/drivers/misc/cxl/irq.c @@ -203,7 +203,6 @@ unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq, void cxl_unmap_irq(unsigned int virq, void *cookie) { free_irq(virq, cookie); - irq_dispose_mapping(virq); } int cxl_register_one_irq(struct cxl *adapter, From 2bc79ffcbb817873cc43d63118008ab75181b73d Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 22 Apr 2016 14:57:49 +1000 Subject: [PATCH 2/3] cxl: Poll for outstanding IRQs when detaching a context When detaching contexts, we may still have interrupts in the system which are yet to be delivered to any CPU and be acked in the PSL. This can result in a subsequent unrelated process getting an spurious IRQ or an interrupt for a non-existent context. This polls the PSL to ensure that the PSL is clear of IRQs for the detached context, before removing the context from the idr. Signed-off-by: Michael Neuling Tested-by: Andrew Donnellan Acked-by: Ian Munsie Tested-by: Vaibhav Jain Signed-off-by: Michael Ellerman --- drivers/misc/cxl/context.c | 7 +++++++ drivers/misc/cxl/cxl.h | 2 ++ drivers/misc/cxl/native.c | 31 +++++++++++++++++++++++++++++++ 3 files changed, 40 insertions(+) diff --git a/drivers/misc/cxl/context.c b/drivers/misc/cxl/context.c index 10370f280500..7edea9c19199 100644 --- a/drivers/misc/cxl/context.c +++ b/drivers/misc/cxl/context.c @@ -223,6 +223,13 @@ int __detach_context(struct cxl_context *ctx) cxl_ops->link_ok(ctx->afu->adapter, ctx->afu)); flush_work(&ctx->fault_work); /* Only needed for dedicated process */ + /* + * Wait until no further interrupts are presented by the PSL + * for this context. + */ + if (cxl_ops->irq_wait) + cxl_ops->irq_wait(ctx); + /* release the reference to the group leader and mm handling pid */ put_pid(ctx->pid); put_pid(ctx->glpid); diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h index 38e21cf7806e..73dc2a33da74 100644 --- a/drivers/misc/cxl/cxl.h +++ b/drivers/misc/cxl/cxl.h @@ -274,6 +274,7 @@ static const cxl_p2n_reg_t CXL_PSL_WED_An = {0x0A0}; #define CXL_PSL_DSISR_An_PE (1ull << (63-4)) /* PSL Error (implementation specific) */ #define CXL_PSL_DSISR_An_AE (1ull << (63-5)) /* AFU Error */ #define CXL_PSL_DSISR_An_OC (1ull << (63-6)) /* OS Context Warning */ +#define CXL_PSL_DSISR_PENDING (CXL_PSL_DSISR_TRANS | CXL_PSL_DSISR_An_PE | CXL_PSL_DSISR_An_AE | CXL_PSL_DSISR_An_OC) /* NOTE: Bits 32:63 are undefined if DSISR[DS] = 1 */ #define CXL_PSL_DSISR_An_M DSISR_NOHPTE /* PTE not found */ #define CXL_PSL_DSISR_An_P DSISR_PROTFAULT /* Storage protection violation */ @@ -855,6 +856,7 @@ struct cxl_backend_ops { u64 dsisr, u64 errstat); irqreturn_t (*psl_interrupt)(int irq, void *data); int (*ack_irq)(struct cxl_context *ctx, u64 tfc, u64 psl_reset_mask); + void (*irq_wait)(struct cxl_context *ctx); int (*attach_process)(struct cxl_context *ctx, bool kernel, u64 wed, u64 amr); int (*detach_process)(struct cxl_context *ctx); diff --git a/drivers/misc/cxl/native.c b/drivers/misc/cxl/native.c index 387fcbdf9793..ecf7557cd657 100644 --- a/drivers/misc/cxl/native.c +++ b/drivers/misc/cxl/native.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -797,6 +798,35 @@ static irqreturn_t native_irq_multiplexed(int irq, void *data) return fail_psl_irq(afu, &irq_info); } +void native_irq_wait(struct cxl_context *ctx) +{ + u64 dsisr; + int timeout = 1000; + int ph; + + /* + * Wait until no further interrupts are presented by the PSL + * for this context. + */ + while (timeout--) { + ph = cxl_p2n_read(ctx->afu, CXL_PSL_PEHandle_An) & 0xffff; + if (ph != ctx->pe) + return; + dsisr = cxl_p2n_read(ctx->afu, CXL_PSL_DSISR_An); + if ((dsisr & CXL_PSL_DSISR_PENDING) == 0) + return; + /* + * We are waiting for the workqueue to process our + * irq, so need to let that run here. + */ + msleep(1); + } + + dev_warn(&ctx->afu->dev, "WARNING: waiting on DSI for PE %i" + " DSISR %016llx!\n", ph, dsisr); + return; +} + static irqreturn_t native_slice_irq_err(int irq, void *data) { struct cxl_afu *afu = data; @@ -1076,6 +1106,7 @@ const struct cxl_backend_ops cxl_native_ops = { .handle_psl_slice_error = native_handle_psl_slice_error, .psl_interrupt = NULL, .ack_irq = native_ack_irq, + .irq_wait = native_irq_wait, .attach_process = native_attach_process, .detach_process = native_detach_process, .support_attributes = native_support_attributes, From d701cca6744fe0d67c86346dcfc9b128b17b5045 Mon Sep 17 00:00:00 2001 From: Rui Salvaterra Date: Tue, 19 Apr 2016 13:23:36 +0100 Subject: [PATCH 3/3] powerpc: wire up preadv2 and pwritev2 syscalls Wire up preadv2/pwritev2 in the same way as preadv/pwritev. Fixes two build warnings on ppc64. mpe: Lightly tested with fio (slightly hacked to add the syscall wrappers): fio-4217 [009] .... 1304.635300: sys_preadv2(fd: 3, vec: 10025821de0, vlen: 1, pos_l: 6253000, pos_h: 0, flags: 1) fio-4217 [009] .... 1304.635474: sys_preadv2 -> 0x1000 Signed-off-by: Rui Salvaterra Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/systbl.h | 2 ++ arch/powerpc/include/asm/unistd.h | 2 +- arch/powerpc/include/uapi/asm/unistd.h | 2 ++ 3 files changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h index 3fa9df70aa20..2fc5d4db503c 100644 --- a/arch/powerpc/include/asm/systbl.h +++ b/arch/powerpc/include/asm/systbl.h @@ -384,3 +384,5 @@ SYSCALL(ni_syscall) SYSCALL(ni_syscall) SYSCALL(mlock2) SYSCALL(copy_file_range) +COMPAT_SYS_SPU(preadv2) +COMPAT_SYS_SPU(pwritev2) diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h index 1f2594d45605..cf12c580f6b2 100644 --- a/arch/powerpc/include/asm/unistd.h +++ b/arch/powerpc/include/asm/unistd.h @@ -12,7 +12,7 @@ #include -#define NR_syscalls 380 +#define NR_syscalls 382 #define __NR__exit __NR_exit diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h index 940290d45b08..e9f5f41aa55a 100644 --- a/arch/powerpc/include/uapi/asm/unistd.h +++ b/arch/powerpc/include/uapi/asm/unistd.h @@ -390,5 +390,7 @@ #define __NR_membarrier 365 #define __NR_mlock2 378 #define __NR_copy_file_range 379 +#define __NR_preadv2 380 +#define __NR_pwritev2 381 #endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */