linux-kernel - Re: [PATCH 2/2] tracing: Document the stack trace algorithm in the comments

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: <20190807124013.4ced2f81@gandalf.local.home>
Date:   Wed, 7 Aug 2019 12:40:13 -0400
From:   Steven Rostedt <rostedt@...dmis.org>
To:     linux-kernel@...r.kernel.org
Cc:     Joel Fernandes <joel@...lfernandes.org>,
        Jiping Ma <jiping.ma2@...driver.com>, mingo@...hat.com,
        catalin.marinas@....com, will.deacon@....com,
        linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH 2/2] tracing: Document the stack trace algorithm in the
 comments

On Wed, 07 Aug 2019 12:34:03 -0400
Steven Rostedt <rostedt@...dmis.org> wrote:

> From: "Steven Rostedt (VMware)" <rostedt@...dmis.org>

> + * To fix this, if the architecture sets ARCH_RET_ADDR_AFTER_LOCAL_VARS the
> + * values in stack_trace_index[] are shifted by one to and the number of
> + * stack trace entries is decremented by one.
> + *
> + *        stack_dump_trace[]        |   stack_trace_index[]
> + *        ------------------        +   -------------------
> + *  return addr to kernel_func_bar  |          20

That should have been 29, not 20. I'll update it.

-- Steve


> + *  return addr to sys_foo          |          19
> + *
> + * Although the entry function is not displayed, the first function (sys_foo)
> + * will still include the stack size of it.
> + */
>  static void check_stack(unsigned long ip, unsigned long *stack)
>  {
>  	unsigned long this_size, flags; unsigned long *p, *top, *start;