From 7682a4c624e0011b5f3e8dd3021dc54961260d97 Mon Sep 17 00:00:00 2001 From: Dean Nelson Date: Tue, 8 Aug 2006 15:03:29 -0500 Subject: [IA64-SGI] Silent data corruption caused by XPC V2. Jack Steiner identified a problem where XPC can cause a silent data corruption. On module load, the placement may cause the xpc_remote_copy_buffer to span two physical pages. DMA transfers are done to the start virtual address translated to physical. This patch changes the buffer from a statically allocated buffer to a kmalloc'd buffer. Dean Nelson reviewed this before posting. I have tested it in the configuration that was showing the memory corruption and verified it works. I also added a BUG_ON statement to help catch this if a similar situation is encountered. Signed-off-by: Robin Holt Signed-off-by: Dean Nelson Signed-off-by: Jack Steiner Signed-off-by: Tony Luck --- include/asm-ia64/sn/xp.h | 22 ++++++++++++++++++---- include/asm-ia64/sn/xpc.h | 4 +++- 2 files changed, 21 insertions(+), 5 deletions(-) (limited to 'include/asm-ia64') diff --git a/include/asm-ia64/sn/xp.h b/include/asm-ia64/sn/xp.h index 9bd2f9bf329b..6f807e0193b7 100644 --- a/include/asm-ia64/sn/xp.h +++ b/include/asm-ia64/sn/xp.h @@ -60,23 +60,37 @@ * the bte_copy() once in the hope that the failure was due to a temporary * aberration (i.e., the link going down temporarily). * - * See bte_copy for definition of the input parameters. + * src - physical address of the source of the transfer. + * vdst - virtual address of the destination of the transfer. + * len - number of bytes to transfer from source to destination. + * mode - see bte_copy() for definition. + * notification - see bte_copy() for definition. * * Note: xp_bte_copy() should never be called while holding a spinlock. */ static inline bte_result_t -xp_bte_copy(u64 src, u64 dest, u64 len, u64 mode, void *notification) +xp_bte_copy(u64 src, u64 vdst, u64 len, u64 mode, void *notification) { bte_result_t ret; + u64 pdst = ia64_tpa(vdst); - ret = bte_copy(src, dest, len, mode, notification); + /* + * Ensure that the physically mapped memory is contiguous. + * + * We do this by ensuring that the memory is from region 7 only. + * If the need should arise to use memory from one of the other + * regions, then modify the BUG_ON() statement to ensure that the + * memory from that region is always physically contiguous. + */ + BUG_ON(REGION_NUMBER(vdst) != RGN_KERNEL); + ret = bte_copy(src, pdst, len, mode, notification); if (ret != BTE_SUCCESS) { if (!in_interrupt()) { cond_resched(); } - ret = bte_copy(src, dest, len, mode, notification); + ret = bte_copy(src, pdst, len, mode, notification); } return ret; diff --git a/include/asm-ia64/sn/xpc.h b/include/asm-ia64/sn/xpc.h index b72af597878d..35e1386f37ab 100644 --- a/include/asm-ia64/sn/xpc.h +++ b/include/asm-ia64/sn/xpc.h @@ -683,7 +683,9 @@ extern struct xpc_vars *xpc_vars; extern struct xpc_rsvd_page *xpc_rsvd_page; extern struct xpc_vars_part *xpc_vars_part; extern struct xpc_partition xpc_partitions[XP_MAX_PARTITIONS + 1]; -extern char xpc_remote_copy_buffer[]; +extern char *xpc_remote_copy_buffer; +extern void *xpc_remote_copy_buffer_base; +extern void *xpc_kmalloc_cacheline_aligned(size_t, gfp_t, void **); extern struct xpc_rsvd_page *xpc_rsvd_page_init(void); extern void xpc_allow_IPI_ops(void); extern void xpc_restrict_IPI_ops(void); -- cgit v1.2.3 From 986e12fa74c837d7fe5bdfe80666e2e2d46711bd Mon Sep 17 00:00:00 2001 From: Russ Anderson Date: Thu, 24 Aug 2006 11:08:52 -0500 Subject: [IA64] remove redundant local_irq_save() calls from sn_sal.h sn_change_memprotect() does a local_irq_save() then calls ia64_sal_oemcall_nolock() which calls SAL_CALL_NOLOCK() which also does a local_irq_save(). This patch removes the redundant local_irq_save() and local_irq_restore() calls in sn_change_memprotect() and sn_inject_error(). Signed-off-by: Russ Anderson Signed-off-by: Tony Luck --- include/asm-ia64/sn/sn_sal.h | 6 ------ 1 file changed, 6 deletions(-) (limited to 'include/asm-ia64') diff --git a/include/asm-ia64/sn/sn_sal.h b/include/asm-ia64/sn/sn_sal.h index bd4452bda357..ba826b3f75bb 100644 --- a/include/asm-ia64/sn/sn_sal.h +++ b/include/asm-ia64/sn/sn_sal.h @@ -706,12 +706,9 @@ static inline int sn_change_memprotect(u64 paddr, u64 len, u64 perms, u64 *nasid_array) { struct ia64_sal_retval ret_stuff; - unsigned long irq_flags; - local_irq_save(irq_flags); ia64_sal_oemcall_nolock(&ret_stuff, SN_SAL_MEMPROTECT, paddr, len, (u64)nasid_array, perms, 0, 0, 0); - local_irq_restore(irq_flags); return ret_stuff.status; } #define SN_MEMPROT_ACCESS_CLASS_0 0x14a080 @@ -1143,12 +1140,9 @@ static inline int sn_inject_error(u64 paddr, u64 *data, u64 *ecc) { struct ia64_sal_retval ret_stuff; - unsigned long irq_flags; - local_irq_save(irq_flags); ia64_sal_oemcall_nolock(&ret_stuff, SN_SAL_INJECT_ERROR, paddr, (u64)data, (u64)ecc, 0, 0, 0, 0); - local_irq_restore(irq_flags); return ret_stuff.status; } -- cgit v1.2.3