From 673d62cc5ea6fca046650f17f77985b112c62322 Mon Sep 17 00:00:00 2001 From: Vegard Nossum Date: Sun, 31 Aug 2008 23:39:21 +0200 Subject: debugobjects: fix lockdep warning Daniel J. Blueman reported: > ======================================================= > [ INFO: possible circular locking dependency detected ] > 2.6.27-rc4-224c #1 > ------------------------------------------------------- > hald/4680 is trying to acquire lock: > (&n->list_lock){++..}, at: [] add_partial+0x26/0x80 > > but task is already holding lock: > (&obj_hash[i].lock){++..}, at: [] > debug_object_free+0x5c/0x120 We fix it by moving the actual freeing to outside the lock (the lock now only protects the list). The pool lock is also promoted to irq-safe (suggested by Dan). It's necessary because free_pool is now called outside the irq disabled region. So we need to protect against an interrupt handler which calls debug_object_init(). [tglx@linutronix.de: added hlist_move_list helper to avoid looping through the list twice] Reported-by: Daniel J Blueman Signed-off-by: Vegard Nossum Signed-off-by: Thomas Gleixner --- lib/debugobjects.c | 31 +++++++++++++++++++++++-------- 1 file changed, 23 insertions(+), 8 deletions(-) (limited to 'lib') diff --git a/lib/debugobjects.c b/lib/debugobjects.c index 45a6bde762d1..e3ab374e1334 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -112,6 +112,7 @@ static struct debug_obj *lookup_object(void *addr, struct debug_bucket *b) /* * Allocate a new object. If the pool is empty, switch off the debugger. + * Must be called with interrupts disabled. */ static struct debug_obj * alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr) @@ -148,17 +149,18 @@ alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr) static void free_object(struct debug_obj *obj) { unsigned long idx = (unsigned long)(obj - obj_static_pool); + unsigned long flags; if (obj_pool_free < ODEBUG_POOL_SIZE || idx < ODEBUG_POOL_SIZE) { - spin_lock(&pool_lock); + spin_lock_irqsave(&pool_lock, flags); hlist_add_head(&obj->node, &obj_pool); obj_pool_free++; obj_pool_used--; - spin_unlock(&pool_lock); + spin_unlock_irqrestore(&pool_lock, flags); } else { - spin_lock(&pool_lock); + spin_lock_irqsave(&pool_lock, flags); obj_pool_used--; - spin_unlock(&pool_lock); + spin_unlock_irqrestore(&pool_lock, flags); kmem_cache_free(obj_cache, obj); } } @@ -171,6 +173,7 @@ static void debug_objects_oom(void) { struct debug_bucket *db = obj_hash; struct hlist_node *node, *tmp; + HLIST_HEAD(freelist); struct debug_obj *obj; unsigned long flags; int i; @@ -179,11 +182,14 @@ static void debug_objects_oom(void) for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) { spin_lock_irqsave(&db->lock, flags); - hlist_for_each_entry_safe(obj, node, tmp, &db->list, node) { + hlist_move_list(&db->list, &freelist); + spin_unlock_irqrestore(&db->lock, flags); + + /* Now free them */ + hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) { hlist_del(&obj->node); free_object(obj); } - spin_unlock_irqrestore(&db->lock, flags); } } @@ -498,8 +504,9 @@ void debug_object_free(void *addr, struct debug_obj_descr *descr) return; default: hlist_del(&obj->node); + spin_unlock_irqrestore(&db->lock, flags); free_object(obj); - break; + return; } out_unlock: spin_unlock_irqrestore(&db->lock, flags); @@ -510,6 +517,7 @@ static void __debug_check_no_obj_freed(const void *address, unsigned long size) { unsigned long flags, oaddr, saddr, eaddr, paddr, chunks; struct hlist_node *node, *tmp; + HLIST_HEAD(freelist); struct debug_obj_descr *descr; enum debug_obj_state state; struct debug_bucket *db; @@ -545,11 +553,18 @@ repeat: goto repeat; default: hlist_del(&obj->node); - free_object(obj); + hlist_add_head(&obj->node, &freelist); break; } } spin_unlock_irqrestore(&db->lock, flags); + + /* Now free them */ + hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) { + hlist_del(&obj->node); + free_object(obj); + } + if (cnt > debug_objects_maxchain) debug_objects_maxchain = cnt; } -- cgit v1.2.3-59-g8ed1b From 7563dc64585324f443f5ac107eb6d89ee813a2d2 Mon Sep 17 00:00:00 2001 From: Tony Breeds Date: Tue, 2 Sep 2008 16:50:38 +1000 Subject: powerpc: Work around gcc's -fno-omit-frame-pointer bug This bug is causing random crashes (http://bugzilla.kernel.org/show_bug.cgi?id=11414). -fno-omit-frame-pointer is only needed on powerpc when -pg is also supplied, and there is a gcc bug that causes incorrect code generation on 32-bit powerpc when -fno-omit-frame-pointer is used---it uses stack locations below the stack pointer, which is not allowed by the ABI because those locations can and sometimes do get corrupted by an interrupt. This ensures that CONFIG_FRAME_POINTER is only selected by ftrace. When CONFIG_FTRACE is enabled we also pass -mno-sched-epilog to work around the gcc codegen bug. Patch based on work by: Andreas Schwab Segher Boessenkool Signed-off-by: Tony Breeds Signed-off-by: Paul Mackerras --- arch/powerpc/Makefile | 5 +++++ arch/powerpc/kernel/Makefile | 7 ++++--- arch/powerpc/platforms/powermac/Makefile | 2 +- lib/Kconfig.debug | 6 +++--- 4 files changed, 13 insertions(+), 7 deletions(-) (limited to 'lib') diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index 9155c9312c1e..c6be19e9ceae 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -116,6 +116,11 @@ ifeq ($(CONFIG_6xx),y) KBUILD_CFLAGS += -mcpu=powerpc endif +# Work around a gcc code-gen bug with -fno-omit-frame-pointer. +ifeq ($(CONFIG_FTRACE),y) +KBUILD_CFLAGS += -mno-sched-epilog +endif + cpu-as-$(CONFIG_4xx) += -Wa,-m405 cpu-as-$(CONFIG_6xx) += -Wa,-maltivec cpu-as-$(CONFIG_POWER4) += -Wa,-maltivec diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 64f5948ebc9d..946daea780f1 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -14,12 +14,13 @@ endif ifdef CONFIG_FTRACE # Do not trace early boot code -CFLAGS_REMOVE_cputable.o = -pg -CFLAGS_REMOVE_prom_init.o = -pg +CFLAGS_REMOVE_cputable.o = -pg -mno-sched-epilog +CFLAGS_REMOVE_prom_init.o = -pg -mno-sched-epilog +CFLAGS_REMOVE_btext.o = -pg -mno-sched-epilog ifdef CONFIG_DYNAMIC_FTRACE # dynamic ftrace setup. -CFLAGS_REMOVE_ftrace.o = -pg +CFLAGS_REMOVE_ftrace.o = -pg -mno-sched-epilog endif endif diff --git a/arch/powerpc/platforms/powermac/Makefile b/arch/powerpc/platforms/powermac/Makefile index 58ecdd72630f..be60d64be7ad 100644 --- a/arch/powerpc/platforms/powermac/Makefile +++ b/arch/powerpc/platforms/powermac/Makefile @@ -2,7 +2,7 @@ CFLAGS_bootx_init.o += -fPIC ifdef CONFIG_FTRACE # Do not trace early boot code -CFLAGS_REMOVE_bootx_init.o = -pg +CFLAGS_REMOVE_bootx_init.o = -pg -mno-sched-epilog endif obj-y += pic.o setup.o time.o feature.o pci.o \ diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 8b5a7d304a5f..0b504814e378 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -394,7 +394,7 @@ config LOCKDEP bool depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT select STACKTRACE - select FRAME_POINTER if !X86 && !MIPS + select FRAME_POINTER if !X86 && !MIPS && !PPC select KALLSYMS select KALLSYMS_ALL @@ -676,13 +676,13 @@ config FAULT_INJECTION_STACKTRACE_FILTER depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT depends on !X86_64 select STACKTRACE - select FRAME_POINTER + select FRAME_POINTER if !PPC help Provide stacktrace filter for fault-injection capabilities config LATENCYTOP bool "Latency measuring infrastructure" - select FRAME_POINTER if !MIPS + select FRAME_POINTER if !MIPS && !PPC select KALLSYMS select KALLSYMS_ALL select STACKTRACE -- cgit v1.2.3-59-g8ed1b From deac93df26b20cf8438339b5935b5f5643bc30c9 Mon Sep 17 00:00:00 2001 From: James Bottomley Date: Wed, 3 Sep 2008 20:43:36 -0500 Subject: lib: Correct printk %pF to work on all architectures It was introduced by "vsprintf: add support for '%pS' and '%pF' pointer formats" in commit 0fe1ef24f7bd0020f29ffe287dfdb9ead33ca0b2. However, the current way its coded doesn't work on parisc64. For two reasons: 1) parisc isn't in the #ifdef and 2) parisc has a different format for function descriptors Make dereference_function_descriptor() more accommodating by allowing architecture overrides. I put the three overrides (for parisc64, ppc64 and ia64) in arch/kernel/module.c because that's where the kernel internal linker which knows how to deal with function descriptors sits. Signed-off-by: James Bottomley Acked-by: Benjamin Herrenschmidt Acked-by: Tony Luck Acked-by: Kyle McMartin Signed-off-by: Linus Torvalds --- arch/ia64/include/asm/sections.h | 3 +++ arch/ia64/kernel/module.c | 12 ++++++++++++ arch/parisc/kernel/module.c | 14 ++++++++++++++ arch/powerpc/include/asm/sections.h | 3 +++ arch/powerpc/kernel/module_64.c | 13 ++++++++++++- include/asm-generic/sections.h | 6 ++++++ include/asm-parisc/sections.h | 5 +++++ lib/vsprintf.c | 11 +---------- 8 files changed, 56 insertions(+), 11 deletions(-) (limited to 'lib') diff --git a/arch/ia64/include/asm/sections.h b/arch/ia64/include/asm/sections.h index 7286e4a9fe84..a7acad2bc2f0 100644 --- a/arch/ia64/include/asm/sections.h +++ b/arch/ia64/include/asm/sections.h @@ -21,5 +21,8 @@ extern char __start_gate_brl_fsys_bubble_down_patchlist[], __end_gate_brl_fsys_b extern char __start_unwind[], __end_unwind[]; extern char __start_ivt_text[], __end_ivt_text[]; +#undef dereference_function_descriptor +void *dereference_function_descriptor(void *); + #endif /* _ASM_IA64_SECTIONS_H */ diff --git a/arch/ia64/kernel/module.c b/arch/ia64/kernel/module.c index 29aad349e0c4..545626f66a4c 100644 --- a/arch/ia64/kernel/module.c +++ b/arch/ia64/kernel/module.c @@ -31,9 +31,11 @@ #include #include #include +#include #include #include +#include #include #define ARCH_MODULE_DEBUG 0 @@ -941,3 +943,13 @@ module_arch_cleanup (struct module *mod) if (mod->arch.core_unw_table) unw_remove_unwind_table(mod->arch.core_unw_table); } + +void *dereference_function_descriptor(void *ptr) +{ + struct fdesc *desc = ptr; + void *p; + + if (!probe_kernel_address(&desc->ip, p)) + ptr = p; + return ptr; +} diff --git a/arch/parisc/kernel/module.c b/arch/parisc/kernel/module.c index fdacdd4341c9..44138c3e6ea7 100644 --- a/arch/parisc/kernel/module.c +++ b/arch/parisc/kernel/module.c @@ -47,7 +47,9 @@ #include #include #include +#include +#include #include #if 0 @@ -860,3 +862,15 @@ void module_arch_cleanup(struct module *mod) deregister_unwind_table(mod); module_bug_cleanup(mod); } + +#ifdef CONFIG_64BIT +void *dereference_function_descriptor(void *ptr) +{ + Elf64_Fdesc *desc = ptr; + void *p; + + if (!probe_kernel_address(&desc->addr, p)) + ptr = p; + return ptr; +} +#endif diff --git a/arch/powerpc/include/asm/sections.h b/arch/powerpc/include/asm/sections.h index 916018e425c4..7710e9e6660f 100644 --- a/arch/powerpc/include/asm/sections.h +++ b/arch/powerpc/include/asm/sections.h @@ -16,6 +16,9 @@ static inline int in_kernel_text(unsigned long addr) return 0; } +#undef dereference_function_descriptor +void *dereference_function_descriptor(void *); + #endif #endif /* __KERNEL__ */ diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c index ee6a2982d567..ad79de272ff3 100644 --- a/arch/powerpc/kernel/module_64.c +++ b/arch/powerpc/kernel/module_64.c @@ -21,8 +21,9 @@ #include #include #include +#include #include -#include +#include #include #include #include @@ -451,3 +452,13 @@ int apply_relocate_add(Elf64_Shdr *sechdrs, return 0; } + +void *dereference_function_descriptor(void *ptr) +{ + struct ppc64_opd_entry *desc = ptr; + void *p; + + if (!probe_kernel_address(&desc->funcaddr, p)) + ptr = p; + return ptr; +} diff --git a/include/asm-generic/sections.h b/include/asm-generic/sections.h index 8feeae1f2369..79a7ff925bf8 100644 --- a/include/asm-generic/sections.h +++ b/include/asm-generic/sections.h @@ -14,4 +14,10 @@ extern char __kprobes_text_start[], __kprobes_text_end[]; extern char __initdata_begin[], __initdata_end[]; extern char __start_rodata[], __end_rodata[]; +/* function descriptor handling (if any). Override + * in asm/sections.h */ +#ifndef dereference_function_descriptor +#define dereference_function_descriptor(p) (p) +#endif + #endif /* _ASM_GENERIC_SECTIONS_H_ */ diff --git a/include/asm-parisc/sections.h b/include/asm-parisc/sections.h index fdd43ec42ec5..9d13c3507ad6 100644 --- a/include/asm-parisc/sections.h +++ b/include/asm-parisc/sections.h @@ -4,4 +4,9 @@ /* nothing to see, move along */ #include +#ifdef CONFIG_64BIT +#undef dereference_function_descriptor +void *dereference_function_descriptor(void *); +#endif + #endif diff --git a/lib/vsprintf.c b/lib/vsprintf.c index d8d1d1142248..c399bc1093cb 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -27,6 +27,7 @@ #include /* for PAGE_SIZE */ #include +#include /* for dereference_function_descriptor() */ /* Works only for digits and letters, but small and fast */ #define TOLOWER(x) ((x) | 0x20) @@ -513,16 +514,6 @@ static char *string(char *buf, char *end, char *s, int field_width, int precisio return buf; } -static inline void *dereference_function_descriptor(void *ptr) -{ -#if defined(CONFIG_IA64) || defined(CONFIG_PPC64) - void *p; - if (!probe_kernel_address(ptr, p)) - ptr = p; -#endif - return ptr; -} - static char *symbol_string(char *buf, char *end, void *ptr, int field_width, int precision, int flags) { unsigned long value = (unsigned long) ptr; -- cgit v1.2.3-59-g8ed1b