linux-kernel - Re: [PATCH] m68knommu: add pretty back strace

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <481B6B3D.9060200@grupopie.com>
Date:	Fri, 02 May 2008 20:27:57 +0100
From:	Paulo Marques <pmarques@...popie.com>
To:	Greg Ungerer <gerg@...pgear.com>
CC:	torvalds@...ux-foundation.org, akpm@...ux-foundation.org,
	gerg@...inux.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] m68knommu: add pretty back strace

Greg Ungerer wrote:
> From: Sebastian Siewior <bigeasy@...utronix.de>
> 
> With this patch and
>  CONFIG_FRAME_POINTER=y
>  CONFIG_KALLSYMS=y
> The backtrace shows resolved function names and their numeric
> address.

This is really not my area, but this patch reminds me of all the dwarf2 
unwinder on x86 that caused so many problems in the beginning...

> [...]
> +#ifdef CONFIG_FRAME_POINTER
> +	printk(KERN_EMERG "Call Trace:\n");
> +
> +	last_stack = stack - 1;
> +	while (stack <= endstack && stack > last_stack) {
> +
> +		addr = *(stack + 1);
> +		printk(KERN_EMERG " [%08lx] ", addr);
> +		print_symbol(KERN_CONT "%s\n", addr);
> +
> +		last_stack = stack;
> +		stack = (unsigned long *)*stack;
>  	}
>  	printk("\n");
> +#else
> +	printk(KERN_EMERG "CONFIG_FRAME_POINTER disabled, no symbolic call trace\n");

You could probably fall back to the old method in this case, no?

Also, if the stack is slightly corrupted on the top, the new method 
might just bail out without giving any indication about the path that 
lead there, when instead it could also fall back to the old method.

-- 
Paulo Marques - www.grupopie.com

"Feed the hungry, save the whales, free the mallocs!"
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/