From: Greg Kroah-Hartman Date: Fri, 7 Sep 2012 17:23:36 +0000 (-0700) Subject: 3.0-stable patches X-Git-Tag: v3.5.4~16 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=f7b90dbafca20f08ae5e28f4405d0c5ce04372cc;p=thirdparty%2Fkernel%2Fstable-queue.git 3.0-stable patches added patches: powerpc-fix-dscr-inheritance-in-copy_thread.patch powerpc-restore-correct-dscr-in-context-switch.patch remove-user-triggerable-bug-from-mpol_to_str.patch --- diff --git a/queue-3.0/powerpc-fix-dscr-inheritance-in-copy_thread.patch b/queue-3.0/powerpc-fix-dscr-inheritance-in-copy_thread.patch new file mode 100644 index 00000000000..7dca2011b60 --- /dev/null +++ b/queue-3.0/powerpc-fix-dscr-inheritance-in-copy_thread.patch @@ -0,0 +1,50 @@ +From 1021cb268b3025573c4811f1dee4a11260c4507b Mon Sep 17 00:00:00 2001 +From: Anton Blanchard +Date: Mon, 3 Sep 2012 16:49:47 +0000 +Subject: powerpc: Fix DSCR inheritance in copy_thread() + +From: Anton Blanchard + +commit 1021cb268b3025573c4811f1dee4a11260c4507b upstream. + +If the default DSCR is non zero we set thread.dscr_inherit in +copy_thread() meaning the new thread and all its children will ignore +future updates to the default DSCR. This is not intended and is +a change in behaviour that a number of our users have hit. + +We just need to inherit thread.dscr and thread.dscr_inherit from +the parent which ends up being much simpler. + +This was found with the following test case: + +http://ozlabs.org/~anton/junkcode/dscr_default_test.c + +Signed-off-by: Anton Blanchard +Signed-off-by: Benjamin Herrenschmidt +Signed-off-by: Greg Kroah-Hartman + +--- + arch/powerpc/kernel/process.c | 12 ++---------- + 1 file changed, 2 insertions(+), 10 deletions(-) + +--- a/arch/powerpc/kernel/process.c ++++ b/arch/powerpc/kernel/process.c +@@ -794,16 +794,8 @@ int copy_thread(unsigned long clone_flag + #endif /* CONFIG_PPC_STD_MMU_64 */ + #ifdef CONFIG_PPC64 + if (cpu_has_feature(CPU_FTR_DSCR)) { +- if (current->thread.dscr_inherit) { +- p->thread.dscr_inherit = 1; +- p->thread.dscr = current->thread.dscr; +- } else if (0 != dscr_default) { +- p->thread.dscr_inherit = 1; +- p->thread.dscr = dscr_default; +- } else { +- p->thread.dscr_inherit = 0; +- p->thread.dscr = 0; +- } ++ p->thread.dscr_inherit = current->thread.dscr_inherit; ++ p->thread.dscr = current->thread.dscr; + } + #endif + diff --git a/queue-3.0/powerpc-restore-correct-dscr-in-context-switch.patch b/queue-3.0/powerpc-restore-correct-dscr-in-context-switch.patch new file mode 100644 index 00000000000..2cd29b54aac --- /dev/null +++ b/queue-3.0/powerpc-restore-correct-dscr-in-context-switch.patch @@ -0,0 +1,99 @@ +From 714332858bfd40dcf8f741498336d93875c23aa7 Mon Sep 17 00:00:00 2001 +From: Anton Blanchard +Date: Mon, 3 Sep 2012 16:51:10 +0000 +Subject: powerpc: Restore correct DSCR in context switch + +From: Anton Blanchard + +commit 714332858bfd40dcf8f741498336d93875c23aa7 upstream. + +During a context switch we always restore the per thread DSCR value. +If we aren't doing explicit DSCR management +(ie thread.dscr_inherit == 0) and the default DSCR changed while +the process has been sleeping we end up with the wrong value. + +Check thread.dscr_inherit and select the default DSCR or per thread +DSCR as required. + +This was found with the following test case, when running with +more threads than CPUs (ie forcing context switching): + +http://ozlabs.org/~anton/junkcode/dscr_default_test.c + +With the four patches applied I can run a combination of all +test cases successfully at the same time: + +http://ozlabs.org/~anton/junkcode/dscr_default_test.c +http://ozlabs.org/~anton/junkcode/dscr_explicit_test.c +http://ozlabs.org/~anton/junkcode/dscr_inherit_test.c + +Signed-off-by: Anton Blanchard +Signed-off-by: Benjamin Herrenschmidt +Signed-off-by: Greg Kroah-Hartman + +--- + arch/powerpc/kernel/asm-offsets.c | 1 + + arch/powerpc/kernel/entry_64.S | 23 +++++++++++++++++------ + 2 files changed, 18 insertions(+), 6 deletions(-) + +--- a/arch/powerpc/kernel/asm-offsets.c ++++ b/arch/powerpc/kernel/asm-offsets.c +@@ -75,6 +75,7 @@ int main(void) + DEFINE(SIGSEGV, SIGSEGV); + DEFINE(NMI_MASK, NMI_MASK); + DEFINE(THREAD_DSCR, offsetof(struct thread_struct, dscr)); ++ DEFINE(THREAD_DSCR_INHERIT, offsetof(struct thread_struct, dscr_inherit)); + #else + DEFINE(THREAD_INFO, offsetof(struct task_struct, stack)); + #endif /* CONFIG_PPC64 */ +--- a/arch/powerpc/kernel/entry_64.S ++++ b/arch/powerpc/kernel/entry_64.S +@@ -380,6 +380,12 @@ _GLOBAL(ret_from_fork) + li r3,0 + b syscall_exit + ++ .section ".toc","aw" ++DSCR_DEFAULT: ++ .tc dscr_default[TC],dscr_default ++ ++ .section ".text" ++ + /* + * This routine switches between two different tasks. The process + * state of one is saved on its kernel stack. Then the state +@@ -519,9 +525,6 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEG + mr r1,r8 /* start using new stack pointer */ + std r7,PACAKSAVE(r13) + +- ld r6,_CCR(r1) +- mtcrf 0xFF,r6 +- + #ifdef CONFIG_ALTIVEC + BEGIN_FTR_SECTION + ld r0,THREAD_VRSAVE(r4) +@@ -530,14 +533,22 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) + #endif /* CONFIG_ALTIVEC */ + #ifdef CONFIG_PPC64 + BEGIN_FTR_SECTION ++ lwz r6,THREAD_DSCR_INHERIT(r4) ++ ld r7,DSCR_DEFAULT@toc(2) + ld r0,THREAD_DSCR(r4) +- cmpd r0,r25 +- beq 1f ++ cmpwi r6,0 ++ bne 1f ++ ld r0,0(r7) ++1: cmpd r0,r25 ++ beq 2f + mtspr SPRN_DSCR,r0 +-1: ++2: + END_FTR_SECTION_IFSET(CPU_FTR_DSCR) + #endif + ++ ld r6,_CCR(r1) ++ mtcrf 0xFF,r6 ++ + /* r3-r13 are destroyed -- Cort */ + REST_8GPRS(14, r1) + REST_10GPRS(22, r1) diff --git a/queue-3.0/remove-user-triggerable-bug-from-mpol_to_str.patch b/queue-3.0/remove-user-triggerable-bug-from-mpol_to_str.patch new file mode 100644 index 00000000000..868996537e5 --- /dev/null +++ b/queue-3.0/remove-user-triggerable-bug-from-mpol_to_str.patch @@ -0,0 +1,42 @@ +From 80de7c3138ee9fd86a98696fd2cf7ad89b995d0a Mon Sep 17 00:00:00 2001 +From: Dave Jones +Date: Thu, 6 Sep 2012 12:01:00 -0400 +Subject: Remove user-triggerable BUG from mpol_to_str + +From: Dave Jones + +commit 80de7c3138ee9fd86a98696fd2cf7ad89b995d0a upstream. + +Trivially triggerable, found by trinity: + + kernel BUG at mm/mempolicy.c:2546! + Process trinity-child2 (pid: 23988, threadinfo ffff88010197e000, task ffff88007821a670) + Call Trace: + show_numa_map+0xd5/0x450 + show_pid_numa_map+0x13/0x20 + traverse+0xf2/0x230 + seq_read+0x34b/0x3e0 + vfs_read+0xac/0x180 + sys_pread64+0xa2/0xc0 + system_call_fastpath+0x1a/0x1f + RIP: mpol_to_str+0x156/0x360 + +Signed-off-by: Dave Jones +Signed-off-by: Linus Torvalds +Signed-off-by: Greg Kroah-Hartman + +--- + mm/mempolicy.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +--- a/mm/mempolicy.c ++++ b/mm/mempolicy.c +@@ -2500,7 +2500,7 @@ int mpol_to_str(char *buffer, int maxlen + break; + + default: +- BUG(); ++ return -EINVAL; + } + + l = strlen(policy_modes[mode]); diff --git a/queue-3.0/series b/queue-3.0/series index 332f3a627ba..9ea42081a41 100644 --- a/queue-3.0/series +++ b/queue-3.0/series @@ -30,3 +30,6 @@ usb-p54usb-remove-__devinit-from-the-struct-usb_device_id-table.patch usb-rtl8187-remove-__devinit-from-the-struct-usb_device_id-table.patch usb-smsusb-remove-__devinit-from-the-struct-usb_device_id-table.patch usb-cdc-acm-fix-null-pointer-dereference.patch +powerpc-fix-dscr-inheritance-in-copy_thread.patch +powerpc-restore-correct-dscr-in-context-switch.patch +remove-user-triggerable-bug-from-mpol_to_str.patch