diff options
Diffstat (limited to 'target/linux/generic/patches-3.8/001-ARM-7668-1-fix-memset-related-crashes-caused-by-rece.patch')
| -rw-r--r-- | target/linux/generic/patches-3.8/001-ARM-7668-1-fix-memset-related-crashes-caused-by-rece.patch | 250 |
1 files changed, 0 insertions, 250 deletions
diff --git a/target/linux/generic/patches-3.8/001-ARM-7668-1-fix-memset-related-crashes-caused-by-rece.patch b/target/linux/generic/patches-3.8/001-ARM-7668-1-fix-memset-related-crashes-caused-by-rece.patch deleted file mode 100644 index 07061b0..0000000 --- a/target/linux/generic/patches-3.8/001-ARM-7668-1-fix-memset-related-crashes-caused-by-rece.patch +++ /dev/null @@ -1,250 +0,0 @@ -From 455bd4c430b0c0a361f38e8658a0d6cb469942b5 Mon Sep 17 00:00:00 2001 -From: Ivan Djelic <ivan.djelic@parrot.com> -Date: Wed, 6 Mar 2013 20:09:27 +0100 -Subject: [PATCH] ARM: 7668/1: fix memset-related crashes caused by recent GCC - (4.7.2) optimizations - -Recent GCC versions (e.g. GCC-4.7.2) perform optimizations based on -assumptions about the implementation of memset and similar functions. -The current ARM optimized memset code does not return the value of -its first argument, as is usually expected from standard implementations. - -For instance in the following function: - -void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter) -{ - memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter)); - waiter->magic = waiter; - INIT_LIST_HEAD(&waiter->list); -} - -compiled as: - -800554d0 <debug_mutex_lock_common>: -800554d0: e92d4008 push {r3, lr} -800554d4: e1a00001 mov r0, r1 -800554d8: e3a02010 mov r2, #16 ; 0x10 -800554dc: e3a01011 mov r1, #17 ; 0x11 -800554e0: eb04426e bl 80165ea0 <memset> -800554e4: e1a03000 mov r3, r0 -800554e8: e583000c str r0, [r3, #12] -800554ec: e5830000 str r0, [r3] -800554f0: e5830004 str r0, [r3, #4] -800554f4: e8bd8008 pop {r3, pc} - -GCC assumes memset returns the value of pointer 'waiter' in register r0; causing -register/memory corruptions. - -This patch fixes the return value of the assembly version of memset. -It adds a 'mov' instruction and merges an additional load+store into -existing load/store instructions. -For ease of review, here is a breakdown of the patch into 4 simple steps: - -Step 1 -====== -Perform the following substitutions: -ip -> r8, then -r0 -> ip, -and insert 'mov ip, r0' as the first statement of the function. -At this point, we have a memset() implementation returning the proper result, -but corrupting r8 on some paths (the ones that were using ip). - -Step 2 -====== -Make sure r8 is saved and restored when (! CALGN(1)+0) == 1: - -save r8: -- str lr, [sp, #-4]! -+ stmfd sp!, {r8, lr} - -and restore r8 on both exit paths: -- ldmeqfd sp!, {pc} @ Now <64 bytes to go. -+ ldmeqfd sp!, {r8, pc} @ Now <64 bytes to go. -(...) - tst r2, #16 - stmneia ip!, {r1, r3, r8, lr} -- ldr lr, [sp], #4 -+ ldmfd sp!, {r8, lr} - -Step 3 -====== -Make sure r8 is saved and restored when (! CALGN(1)+0) == 0: - -save r8: -- stmfd sp!, {r4-r7, lr} -+ stmfd sp!, {r4-r8, lr} - -and restore r8 on both exit paths: - bgt 3b -- ldmeqfd sp!, {r4-r7, pc} -+ ldmeqfd sp!, {r4-r8, pc} -(...) - tst r2, #16 - stmneia ip!, {r4-r7} -- ldmfd sp!, {r4-r7, lr} -+ ldmfd sp!, {r4-r8, lr} - -Step 4 -====== -Rewrite register list "r4-r7, r8" as "r4-r8". - -Signed-off-by: Ivan Djelic <ivan.djelic@parrot.com> -Reviewed-by: Nicolas Pitre <nico@linaro.org> -Signed-off-by: Dirk Behme <dirk.behme@gmail.com> -Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> ---- - arch/arm/lib/memset.S | 85 ++++++++++++++++++++++++++------------------------- - 1 file changed, 44 insertions(+), 41 deletions(-) - ---- a/arch/arm/lib/memset.S -+++ b/arch/arm/lib/memset.S -@@ -19,9 +19,9 @@ - 1: subs r2, r2, #4 @ 1 do we have enough - blt 5f @ 1 bytes to align with? - cmp r3, #2 @ 1 -- strltb r1, [r0], #1 @ 1 -- strleb r1, [r0], #1 @ 1 -- strb r1, [r0], #1 @ 1 -+ strltb r1, [ip], #1 @ 1 -+ strleb r1, [ip], #1 @ 1 -+ strb r1, [ip], #1 @ 1 - add r2, r2, r3 @ 1 (r2 = r2 - (4 - r3)) - /* - * The pointer is now aligned and the length is adjusted. Try doing the -@@ -29,10 +29,14 @@ - */ - - ENTRY(memset) -- ands r3, r0, #3 @ 1 unaligned? -+/* -+ * Preserve the contents of r0 for the return value. -+ */ -+ mov ip, r0 -+ ands r3, ip, #3 @ 1 unaligned? - bne 1b @ 1 - /* -- * we know that the pointer in r0 is aligned to a word boundary. -+ * we know that the pointer in ip is aligned to a word boundary. - */ - orr r1, r1, r1, lsl #8 - orr r1, r1, r1, lsl #16 -@@ -43,29 +47,28 @@ ENTRY(memset) - #if ! CALGN(1)+0 - - /* -- * We need an extra register for this loop - save the return address and -- * use the LR -+ * We need 2 extra registers for this loop - use r8 and the LR - */ -- str lr, [sp, #-4]! -- mov ip, r1 -+ stmfd sp!, {r8, lr} -+ mov r8, r1 - mov lr, r1 - - 2: subs r2, r2, #64 -- stmgeia r0!, {r1, r3, ip, lr} @ 64 bytes at a time. -- stmgeia r0!, {r1, r3, ip, lr} -- stmgeia r0!, {r1, r3, ip, lr} -- stmgeia r0!, {r1, r3, ip, lr} -+ stmgeia ip!, {r1, r3, r8, lr} @ 64 bytes at a time. -+ stmgeia ip!, {r1, r3, r8, lr} -+ stmgeia ip!, {r1, r3, r8, lr} -+ stmgeia ip!, {r1, r3, r8, lr} - bgt 2b -- ldmeqfd sp!, {pc} @ Now <64 bytes to go. -+ ldmeqfd sp!, {r8, pc} @ Now <64 bytes to go. - /* - * No need to correct the count; we're only testing bits from now on - */ - tst r2, #32 -- stmneia r0!, {r1, r3, ip, lr} -- stmneia r0!, {r1, r3, ip, lr} -+ stmneia ip!, {r1, r3, r8, lr} -+ stmneia ip!, {r1, r3, r8, lr} - tst r2, #16 -- stmneia r0!, {r1, r3, ip, lr} -- ldr lr, [sp], #4 -+ stmneia ip!, {r1, r3, r8, lr} -+ ldmfd sp!, {r8, lr} - - #else - -@@ -74,54 +77,54 @@ ENTRY(memset) - * whole cache lines at once. - */ - -- stmfd sp!, {r4-r7, lr} -+ stmfd sp!, {r4-r8, lr} - mov r4, r1 - mov r5, r1 - mov r6, r1 - mov r7, r1 -- mov ip, r1 -+ mov r8, r1 - mov lr, r1 - - cmp r2, #96 -- tstgt r0, #31 -+ tstgt ip, #31 - ble 3f - -- and ip, r0, #31 -- rsb ip, ip, #32 -- sub r2, r2, ip -- movs ip, ip, lsl #(32 - 4) -- stmcsia r0!, {r4, r5, r6, r7} -- stmmiia r0!, {r4, r5} -- tst ip, #(1 << 30) -- mov ip, r1 -- strne r1, [r0], #4 -+ and r8, ip, #31 -+ rsb r8, r8, #32 -+ sub r2, r2, r8 -+ movs r8, r8, lsl #(32 - 4) -+ stmcsia ip!, {r4, r5, r6, r7} -+ stmmiia ip!, {r4, r5} -+ tst r8, #(1 << 30) -+ mov r8, r1 -+ strne r1, [ip], #4 - - 3: subs r2, r2, #64 -- stmgeia r0!, {r1, r3-r7, ip, lr} -- stmgeia r0!, {r1, r3-r7, ip, lr} -+ stmgeia ip!, {r1, r3-r8, lr} -+ stmgeia ip!, {r1, r3-r8, lr} - bgt 3b -- ldmeqfd sp!, {r4-r7, pc} -+ ldmeqfd sp!, {r4-r8, pc} - - tst r2, #32 -- stmneia r0!, {r1, r3-r7, ip, lr} -+ stmneia ip!, {r1, r3-r8, lr} - tst r2, #16 -- stmneia r0!, {r4-r7} -- ldmfd sp!, {r4-r7, lr} -+ stmneia ip!, {r4-r7} -+ ldmfd sp!, {r4-r8, lr} - - #endif - - 4: tst r2, #8 -- stmneia r0!, {r1, r3} -+ stmneia ip!, {r1, r3} - tst r2, #4 -- strne r1, [r0], #4 -+ strne r1, [ip], #4 - /* - * When we get here, we've got less than 4 bytes to zero. We - * may have an unaligned pointer as well. - */ - 5: tst r2, #2 -- strneb r1, [r0], #1 -- strneb r1, [r0], #1 -+ strneb r1, [ip], #1 -+ strneb r1, [ip], #1 - tst r2, #1 -- strneb r1, [r0], #1 -+ strneb r1, [ip], #1 - mov pc, lr - ENDPROC(memset) |