Messages in this thread | | | Subject | Re: [PATCH v4 5/6] powerpc: Add show_user_instructions() | From | Christophe LEROY <> | Date | Thu, 2 Aug 2018 07:26:20 +0200 |
| |
Le 01/08/2018 à 23:33, Murilo Opsfelder Araujo a écrit : > show_user_instructions() is a slightly modified version of > show_instructions() that allows userspace instruction dump. > > This will be useful within show_signal_msg() to dump userspace > instructions of the faulty location. > > Here is a sample of what show_user_instructions() outputs: > > pandafault[10850]: code: 4bfffeec 4bfffee8 3c401002 38427f00 fbe1fff8 f821ffc1 7c3f0b78 3d22fffe > pandafault[10850]: code: 392988d0 f93f0020 e93f0020 39400048 <99490000> 39200000 7d234b78 383f0040 > > The current->comm and current->pid printed can serve as a glue that > links the instructions dump to its originator, allowing messages to be > interleaved in the logs. > > Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com> > --- > arch/powerpc/include/asm/stacktrace.h | 13 +++++++++ > arch/powerpc/kernel/process.c | 40 +++++++++++++++++++++++++++ > 2 files changed, 53 insertions(+) > create mode 100644 arch/powerpc/include/asm/stacktrace.h > > diff --git a/arch/powerpc/include/asm/stacktrace.h b/arch/powerpc/include/asm/stacktrace.h > new file mode 100644 > index 000000000000..6149b53b3bc8 > --- /dev/null > +++ b/arch/powerpc/include/asm/stacktrace.h > @@ -0,0 +1,13 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Stack trace functions. > + * > + * Copyright 2018, Murilo Opsfelder Araujo, IBM Corporation. > + */ > + > +#ifndef _ASM_POWERPC_STACKTRACE_H > +#define _ASM_POWERPC_STACKTRACE_H > + > +void show_user_instructions(struct pt_regs *regs); > + > +#endif /* _ASM_POWERPC_STACKTRACE_H */ > diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c > index e9533b4d2f08..364645ac732c 100644 > --- a/arch/powerpc/kernel/process.c > +++ b/arch/powerpc/kernel/process.c > @@ -1299,6 +1299,46 @@ static void show_instructions(struct pt_regs *regs) > pr_cont("\n"); > } > > +void show_user_instructions(struct pt_regs *regs) > +{ > + int i; > + const char *prefix = KERN_INFO "%s[%d]: code: "; > + unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 * > + sizeof(int)); > + > + printk(prefix, current->comm, current->pid);
Why not use pr_info() and remove KERN_INFO from *prefix ?
> + > + for (i = 0; i < instructions_to_print; i++) { > + int instr; > + > + if (!(i % 8) && (i > 0)) { > + pr_cont("\n"); > + printk(prefix, current->comm, current->pid); > + } > + > +#if !defined(CONFIG_BOOKE) > + /* If executing with the IMMU off, adjust pc rather > + * than print XXXXXXXX. > + */ > + if (!(regs->msr & MSR_IR)) > + pc = (unsigned long)phys_to_virt(pc);
Shouldn't this be done outside of the loop, only once ?
Christophe
> +#endif > + > + if (probe_kernel_address((unsigned int __user *)pc, instr)) { > + pr_cont("XXXXXXXX "); > + } else { > + if (regs->nip == pc) > + pr_cont("<%08x> ", instr); > + else > + pr_cont("%08x ", instr); > + } > + > + pc += sizeof(int); > + } > + > + pr_cont("\n"); > +} > + > struct regbit { > unsigned long bit; > const char *name; >
| |