Re: [PATCH 8/9] x86/dumpstack: Save first regs set for the executive summary

From: Josh Poimboeuf
Date: Thu Mar 15 2018 - 15:01:39 EST


On Thu, Mar 15, 2018 at 04:44:47PM +0100, Borislav Petkov wrote:
> @@ -321,6 +323,9 @@ void oops_end(unsigned long flags, struct pt_regs *regs, int signr)
> raw_local_irq_restore(flags);
> oops_exit();
>
> + /* Executive summary in case the oops scrolled away */
> + __show_regs(&exec_summary_regs, false);
> +

no_context() has the following line, right before it calls oops_end():

/* Executive summary in case the body of the oops scrolled away */
printk(KERN_DEFAULT "CR2: %016lx\n", address);

I think that line can now be removed, since the executive summary
__show_regs() will include CR2.


> @@ -352,26 +357,14 @@ int __die(const char *str, struct pt_regs *regs, long err)
> IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION) ?
> (boot_cpu_has(X86_FEATURE_PTI) ? " PTI" : " NOPTI") : "");
>
> + show_regs(regs);
> +
> if (notify_die(DIE_OOPS, str, regs, err,
> current->thread.trap_nr, SIGSEGV) == NOTIFY_STOP)
> return 1;
>
> print_modules();
> - show_regs(regs);

Was moving the show_regs() call intentional? I didn't see it mentioned
in the changelog.

> @@ -410,7 +403,5 @@ void show_regs(struct pt_regs *regs)
>
> if (regs->ip < PAGE_OFFSET)
> pr_cont(" Bad RIP value.\n");
> - else
> - show_opcodes((u8 *)regs->ip, KERN_DEFAULT);
> }
> }

Doesn't this hunk belong in the previous patch, which added the
__show_regs -> show_ip() -> show_opcodes() call path?

--
Josh