From 73c9ceab40b1269d6195e556773167c078ac8311 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 8 Dec 2006 03:30:41 -0800 Subject: [POWERPC] Generic BUG for powerpc This makes powerpc use the generic BUG machinery. The biggest reports the function name, since it is redundant with kallsyms, and not needed in general. There is an overall reduction of code, since module_32/64 duplicated several functions. Unfortunately there's no way to tell gcc that BUG won't return, so the BUG macro includes a goto loop. This will generate a real jmp instruction, which is never used. [akpm@osdl.org: build fix] [paulus@samba.org: remove infinite loop in BUG_ON] Signed-off-by: Jeremy Fitzhardinge Cc: Andi Kleen Cc: Hugh Dickens Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Paul Mackerras --- arch/powerpc/Kconfig | 5 ++++ arch/powerpc/kernel/module_32.c | 23 +++++------------ arch/powerpc/kernel/module_64.c | 23 +++++------------ arch/powerpc/kernel/traps.c | 54 +++++---------------------------------- arch/powerpc/kernel/vmlinux.lds.S | 6 +---- arch/powerpc/xmon/xmon.c | 10 ++++---- 6 files changed, 29 insertions(+), 92 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index a35212b7346..f81d9f6f19f 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -99,6 +99,11 @@ config AUDIT_ARCH bool default y +config GENERIC_BUG + bool + default y + depends on BUG + config DEFAULT_UIMAGE bool help diff --git a/arch/powerpc/kernel/module_32.c b/arch/powerpc/kernel/module_32.c index e2c3c6a85f3..8339fd609de 100644 --- a/arch/powerpc/kernel/module_32.c +++ b/arch/powerpc/kernel/module_32.c @@ -23,6 +23,7 @@ #include #include #include +#include #include "setup.h" @@ -290,23 +291,11 @@ int module_finalize(const Elf_Ehdr *hdr, struct module *me) { const Elf_Shdr *sect; + int err; - me->arch.bug_table = NULL; - me->arch.num_bugs = 0; - - /* Find the __bug_table section, if present */ - sect = find_section(hdr, sechdrs, "__bug_table"); - if (sect != NULL) { - me->arch.bug_table = (void *) sect->sh_addr; - me->arch.num_bugs = sect->sh_size / sizeof(struct bug_entry); - } - - /* - * Strictly speaking this should have a spinlock to protect against - * traversals, but since we only traverse on BUG()s, a spinlock - * could potentially lead to deadlock and thus be counter-productive. - */ - list_add(&me->arch.bug_list, &module_bug_list); + err = module_bug_finalize(hdr, sechdrs, me); + if (err) /* never true, currently */ + return err; /* Apply feature fixups */ sect = find_section(hdr, sechdrs, "__ftr_fixup"); @@ -320,7 +309,7 @@ int module_finalize(const Elf_Ehdr *hdr, void module_arch_cleanup(struct module *mod) { - list_del(&mod->arch.bug_list); + module_bug_cleanup(mod); } struct bug_entry *module_find_bug(unsigned long bugaddr) diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c index 8dd1f0aae5d..75c7c4f1928 100644 --- a/arch/powerpc/kernel/module_64.c +++ b/arch/powerpc/kernel/module_64.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -439,23 +440,11 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, struct module *me) { const Elf_Shdr *sect; + int err; - me->arch.bug_table = NULL; - me->arch.num_bugs = 0; - - /* Find the __bug_table section, if present */ - sect = find_section(hdr, sechdrs, "__bug_table"); - if (sect != NULL) { - me->arch.bug_table = (void *) sect->sh_addr; - me->arch.num_bugs = sect->sh_size / sizeof(struct bug_entry); - } - - /* - * Strictly speaking this should have a spinlock to protect against - * traversals, but since we only traverse on BUG()s, a spinlock - * could potentially lead to deadlock and thus be counter-productive. - */ - list_add(&me->arch.bug_list, &module_bug_list); + err = module_bug_finalize(hdr, sechdrs, me); + if (err) + return err; /* Apply feature fixups */ sect = find_section(hdr, sechdrs, "__ftr_fixup"); @@ -475,7 +464,7 @@ int module_finalize(const Elf_Ehdr *hdr, void module_arch_cleanup(struct module *mod) { - list_del(&mod->arch.bug_list); + module_bug_cleanup(mod); } struct bug_entry *module_find_bug(unsigned long bugaddr) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index fde820e52d0..535f5066564 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -727,54 +728,9 @@ static int emulate_instruction(struct pt_regs *regs) return -EINVAL; } -/* - * Look through the list of trap instructions that are used for BUG(), - * BUG_ON() and WARN_ON() and see if we hit one. At this point we know - * that the exception was caused by a trap instruction of some kind. - * Returns 1 if we should continue (i.e. it was a WARN_ON) or 0 - * otherwise. - */ -extern struct bug_entry __start___bug_table[], __stop___bug_table[]; - -#ifndef CONFIG_MODULES -#define module_find_bug(x) NULL -#endif - -struct bug_entry *find_bug(unsigned long bugaddr) +int is_valid_bugaddr(unsigned long addr) { - struct bug_entry *bug; - - for (bug = __start___bug_table; bug < __stop___bug_table; ++bug) - if (bugaddr == bug->bug_addr) - return bug; - return module_find_bug(bugaddr); -} - -static int check_bug_trap(struct pt_regs *regs) -{ - struct bug_entry *bug; - unsigned long addr; - - if (regs->msr & MSR_PR) - return 0; /* not in kernel */ - addr = regs->nip; /* address of trap instruction */ - if (addr < PAGE_OFFSET) - return 0; - bug = find_bug(regs->nip); - if (bug == NULL) - return 0; - if (bug->line & BUG_WARNING_TRAP) { - /* this is a WARN_ON rather than BUG/BUG_ON */ - printk(KERN_ERR "Badness in %s at %s:%ld\n", - bug->function, bug->file, - bug->line & ~BUG_WARNING_TRAP); - dump_stack(); - return 1; - } - printk(KERN_CRIT "kernel BUG in %s at %s:%ld!\n", - bug->function, bug->file, bug->line); - - return 0; + return is_kernel_addr(addr); } void __kprobes program_check_exception(struct pt_regs *regs) @@ -810,7 +766,9 @@ void __kprobes program_check_exception(struct pt_regs *regs) return; if (debugger_bpt(regs)) return; - if (check_bug_trap(regs)) { + + if (!(regs->msr & MSR_PR) && /* not user-mode */ + report_bug(regs->nip) == BUG_TRAP_TYPE_WARN) { regs->nip += 4; return; } diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 04b98671a06..04b8e71bf5b 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -62,11 +62,7 @@ SECTIONS __stop___ex_table = .; } - __bug_table : { - __start___bug_table = .; - *(__bug_table) - __stop___bug_table = .; - } + BUG_TABLE /* * Init sections discarded at runtime diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index a34ed49e035..77540a2f770 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include @@ -35,7 +36,6 @@ #include #include #include -#include #include #include #include @@ -1346,7 +1346,7 @@ static void backtrace(struct pt_regs *excp) static void print_bug_trap(struct pt_regs *regs) { - struct bug_entry *bug; + const struct bug_entry *bug; unsigned long addr; if (regs->msr & MSR_PR) @@ -1357,11 +1357,11 @@ static void print_bug_trap(struct pt_regs *regs) bug = find_bug(regs->nip); if (bug == NULL) return; - if (bug->line & BUG_WARNING_TRAP) + if (is_warning_bug(bug)) return; - printf("kernel BUG in %s at %s:%d!\n", - bug->function, bug->file, (unsigned int)bug->line); + printf("kernel BUG at %s:%u!\n", + bug->file, bug->line); } void excprint(struct pt_regs *fp) -- cgit v1.2.3