From: Dmitry Safonov <dsafonov@virtuozzo.com>
To: Oleg Nesterov <oleg@redhat.com>
Cc: <linux-kernel@vger.kernel.org>, <mingo@redhat.com>,
<luto@amacapital.net>, <tglx@linutronix.de>, <hpa@zytor.com>,
<x86@kernel.org>, <0x7f454c46@gmail.com>, <gorcunov@openvz.org>,
<xemul@virtuozzo.com>, <khorenko@virtuozzo.com>,
Andy Lutomirski <luto@kernel.org>,
Alexander Viro <viro@zeniv.linux.org.uk>,
<linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH 4/6] x86/coredump: use core regs, rather that TIF_IA32 flag
Date: Wed, 8 Jun 2016 16:28:57 +0300 [thread overview]
Message-ID: <42fcbe2c-8436-7f0a-054f-24ef66f57b7a@virtuozzo.com> (raw)
In-Reply-To: <20160606224336.GA30331@redhat.com>
On 06/07/2016 01:43 AM, Oleg Nesterov wrote:
> On 06/06, Oleg Nesterov wrote:
>>
>> On 06/01, Dmitry Safonov wrote:
>>>
>>> static int fill_thread_core_info(struct elf_thread_core_info *t,
>>> const struct user_regset_view *view,
>>> - long signr, size_t *total)
>>> + long signr, size_t *total,
>>> + struct pt_regs *regs __maybe_unused)
>>> {
>>> unsigned int i;
>>>
>>> @@ -1652,11 +1653,11 @@ static int fill_thread_core_info(struct elf_thread_core_info *t,
>>> */
>>> fill_prstatus(&t->prstatus, t->task, signr);
>>> (void) view->regsets[0].get(t->task, &view->regsets[0],
>>> - 0, PR_REG_SIZE(t->prstatus.pr_reg),
>>> + 0, PR_REG_SIZE(t->prstatus.pr_reg, regs),
>>
>> Hmm. I don't understand this... Note that this "regs" argument has nothing
>> to do with t->task if the process is multithreaded,
>>
>>> @@ -1772,7 +1773,8 @@ static int fill_note_info(struct elfhdr *elf, int phdrs,
>>> * Now fill in each thread's information.
>>> */
>>> for (t = info->thread; t != NULL; t = t->next)
>>> - if (!fill_thread_core_info(t, view, siginfo->si_signo, &info->size))
>>> + if (!fill_thread_core_info(t, view, siginfo->si_signo,
>>> + &info->size, regs))
>>
>> fill_note_info(..., args) is called with args = task_pt_regs(dumper_thread).
>
> forgot to mention... yes, this matches the fact we use a single "view"
> for all threads, and we get it via task_user_regset_view(dump_task).
>
> But this change (imo) adds even more confusion, and without the next patch
> the logic looks "obviously wrong", becauase PR_REG_SIZE/etc look at
> dumper_thread->cs while task_user_regset_view() checks thread flags.
>
> Anyway I fail to understand these macros... Say, PR_REG_SIZE(S). Can't we
> kill it and use regsets[0].n * regsets[0].size instead ? These numbers
> should match whatever we do, if we call ->get().
>
Thanks, the idea of dropping PR_REG_SIZE looks better than my patch!
I'll try to drop those macros for the next revision.
--
Regards,
Dmitry Safonov
next prev parent reply other threads:[~2016-06-08 13:30 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-01 13:11 [PATCH 0/6] x86: 32-bit compatible C/R on x86_64 Dmitry Safonov
2016-06-01 13:11 ` [PATCH 1/6] x86/vdso: unmap vdso blob on vvar mapping failure Dmitry Safonov
2016-06-01 13:11 ` [PATCH 2/6] x86/vdso: introduce do_map_vdso() and vdso_type enum Dmitry Safonov
2016-06-03 9:50 ` Cyrill Gorcunov
2016-06-03 10:03 ` Dmitry Safonov
2016-06-01 13:11 ` [PATCH 3/6] x86/arch_prctl/vdso: add ARCH_MAP_VDSO_* Dmitry Safonov
2016-06-01 13:11 ` [PATCH 4/6] x86/coredump: use core regs, rather that TIF_IA32 flag Dmitry Safonov
2016-06-03 9:51 ` Cyrill Gorcunov
2016-06-03 9:56 ` Dmitry Safonov
2016-06-03 10:01 ` Cyrill Gorcunov
2016-06-06 20:45 ` Oleg Nesterov
2016-06-06 22:43 ` Oleg Nesterov
2016-06-08 13:28 ` Dmitry Safonov [this message]
2016-06-01 13:11 ` [PATCH 5/6] x86/ptrace: down with test_thread_flag(TIF_IA32) Dmitry Safonov
2016-06-03 9:57 ` Cyrill Gorcunov
2016-06-03 10:27 ` Dmitry Safonov
2016-06-03 10:41 ` Cyrill Gorcunov
2016-06-06 21:19 ` Oleg Nesterov
2016-06-07 11:38 ` Dmitry Safonov
2016-06-09 17:21 ` Andy Lutomirski
2016-06-10 20:07 ` Oleg Nesterov
2016-06-10 20:14 ` Andy Lutomirski
2016-06-13 13:50 ` Oleg Nesterov
2016-06-13 20:40 ` Andy Lutomirski
2016-06-14 14:34 ` Oleg Nesterov
2016-06-14 14:43 ` Dmitry Safonov
2016-06-01 13:11 ` [PATCH 6/6] x86/signal: add SA_{X32,IA32}_ABI sa_flags Dmitry Safonov
2016-06-04 5:08 ` Andy Lutomirski
2016-06-04 15:57 ` Dmitry Safonov
2016-06-01 13:15 ` [PATCH 0/6] x86: 32-bit compatible C/R on x86_64 Dmitry Safonov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=42fcbe2c-8436-7f0a-054f-24ef66f57b7a@virtuozzo.com \
--to=dsafonov@virtuozzo.com \
--cc=0x7f454c46@gmail.com \
--cc=gorcunov@openvz.org \
--cc=hpa@zytor.com \
--cc=khorenko@virtuozzo.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@amacapital.net \
--cc=luto@kernel.org \
--cc=mingo@redhat.com \
--cc=oleg@redhat.com \
--cc=tglx@linutronix.de \
--cc=viro@zeniv.linux.org.uk \
--cc=x86@kernel.org \
--cc=xemul@virtuozzo.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).