From 4992adfafb41fc41427935911378210ac3243229 Mon Sep 17 00:00:00 2001 From: San Mehat Date: Tue, 25 Aug 2009 16:52:22 -0700 Subject: [PATCH] [ARM] process: Add display of memory around registers when displaying regs. This is extremely useful in diagnosing remote crashes, and is based heavily on original work by . Signed-off-by: San Mehat Cc: Michael Davidson [ARM] process: Use uber-safe probe_kernel_address() to read mem when dumping. This prevents the dump from taking pagefaults / external aborts. Signed-off-by: San Mehat --- arch/arm/kernel/process.c | 73 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 0d96d0171c05..3b1aac1da0bd 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -206,6 +206,77 @@ void machine_restart(char *cmd) arm_pm_restart(reboot_mode, cmd); } +/* + * dump a block of kernel memory from around the given address + */ +static void show_data(unsigned long addr, int nbytes, const char *name) +{ + int i, j; + int nlines; + u32 *p; + + /* + * don't attempt to dump non-kernel addresses or + * values that are probably just small negative numbers + */ + if (addr < PAGE_OFFSET || addr > -256UL) + return; + + printk("\n%s: %#lx:\n", name, addr); + + /* + * round address down to a 32 bit boundary + * and always dump a multiple of 32 bytes + */ + p = (u32 *)(addr & ~(sizeof(u32) - 1)); + nbytes += (addr & (sizeof(u32) - 1)); + nlines = (nbytes + 31) / 32; + + + for (i = 0; i < nlines; i++) { + /* + * just display low 16 bits of address to keep + * each line of the dump < 80 characters + */ + printk("%04lx ", (unsigned long)p & 0xffff); + for (j = 0; j < 8; j++) { + u32 data; + if (probe_kernel_address(p, data)) { + printk(" ********"); + } else { + printk(" %08x", data); + } + ++p; + } + printk("\n"); + } +} + +static void show_extra_register_data(struct pt_regs *regs, int nbytes) +{ + mm_segment_t fs; + + fs = get_fs(); + set_fs(KERNEL_DS); + show_data(regs->ARM_pc - nbytes, nbytes * 2, "PC"); + show_data(regs->ARM_lr - nbytes, nbytes * 2, "LR"); + show_data(regs->ARM_sp - nbytes, nbytes * 2, "SP"); + show_data(regs->ARM_ip - nbytes, nbytes * 2, "IP"); + show_data(regs->ARM_fp - nbytes, nbytes * 2, "FP"); + show_data(regs->ARM_r0 - nbytes, nbytes * 2, "R0"); + show_data(regs->ARM_r1 - nbytes, nbytes * 2, "R1"); + show_data(regs->ARM_r2 - nbytes, nbytes * 2, "R2"); + show_data(regs->ARM_r3 - nbytes, nbytes * 2, "R3"); + show_data(regs->ARM_r4 - nbytes, nbytes * 2, "R4"); + show_data(regs->ARM_r5 - nbytes, nbytes * 2, "R5"); + show_data(regs->ARM_r6 - nbytes, nbytes * 2, "R6"); + show_data(regs->ARM_r7 - nbytes, nbytes * 2, "R7"); + show_data(regs->ARM_r8 - nbytes, nbytes * 2, "R8"); + show_data(regs->ARM_r9 - nbytes, nbytes * 2, "R9"); + show_data(regs->ARM_r10 - nbytes, nbytes * 2, "R10"); + set_fs(fs); +} + void __show_regs(struct pt_regs *regs) { unsigned long flags; @@ -264,6 +335,8 @@ void __show_regs(struct pt_regs *regs) printk("Control: %08x%s\n", ctrl, buf); } #endif + + show_extra_register_data(regs, 128); } void show_regs(struct pt_regs * regs) -- 2.34.1