From: Thomas Gleixner <tglx@linutronix.de>
To: Andy Lutomirski <luto@kernel.org>, x86@kernel.org
Cc: LKML <linux-kernel@vger.kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Brian Gerst <brgerst@gmail.com>,
Andy Lutomirski <luto@kernel.org>,
Josh Poimboeuf <jpoimboe@redhat.com>
Subject: Re: [PATCH v4 3/9] x86/entry: Convert ret_from_fork to C
Date: Fri, 19 Mar 2021 17:05:27 +0100 [thread overview]
Message-ID: <87v99n5dtk.fsf@nanos.tec.linutronix.de> (raw)
In-Reply-To: <f7ed7fa5b222afa2d2820e1d8c83fdc3fdd57af2.1616004689.git.luto@kernel.org>
On Wed, Mar 17 2021 at 11:12, Andy Lutomirski wrote:
> ret_from_fork is written in asm, slightly differently, for x86_32 and
> x86_64. Convert it to C.
> +__visible void noinstr ret_from_fork(struct task_struct *prev,
> + int (*kernel_thread_fn)(void *),
> + void *kernel_thread_arg,
> + struct pt_regs *user_regs)
> +{
> + instrumentation_begin();
> +
> + schedule_tail(prev);
> +
> + if (kernel_thread_fn) {
> + kernel_thread_fn(kernel_thread_arg);
> + user_regs->ax = 0;
If you replace this with:
syscall_set_return_value(current, user_regs, 0, 0);
then it's architecture agnostic and can move to kernel/entry, no?
Thanks,
tglx
next prev parent reply other threads:[~2021-03-19 16:06 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-17 18:12 [PATCH v4 0/9] kentry: A stable bugfix and a bunch of improvements Andy Lutomirski
2021-03-17 18:12 ` [PATCH v4 1/9] x86/dumpstack: Remove unnecessary range check fetching opcode bytes Andy Lutomirski
2021-03-17 18:12 ` [PATCH v4 2/9] x86/kthread,dumpstack: Set task_pt_regs->cs.RPL=3 for kernel threads Andy Lutomirski
2021-03-18 0:36 ` Josh Poimboeuf
2021-03-17 18:12 ` [PATCH v4 3/9] x86/entry: Convert ret_from_fork to C Andy Lutomirski
2021-03-18 0:38 ` Josh Poimboeuf
2021-03-19 16:05 ` Thomas Gleixner [this message]
2021-03-17 18:12 ` [PATCH v4 4/9] kentry: Simplify the common syscall API Andy Lutomirski
2021-03-19 16:09 ` Thomas Gleixner
2021-03-19 18:07 ` Thomas Gleixner
2021-03-17 18:12 ` [PATCH v4 5/9] kentry: Remove enter_from/exit_to_user_mode() Andy Lutomirski
2021-03-19 18:08 ` Thomas Gleixner
2021-03-17 18:12 ` [PATCH v4 6/9] entry: Make CONFIG_DEBUG_ENTRY available outside x86 Andy Lutomirski
2021-03-17 18:12 ` [PATCH v4 7/9] kentry: Add debugging checks for proper kentry API usage Andy Lutomirski
2021-03-19 16:17 ` Thomas Gleixner
2021-03-19 18:16 ` Thomas Gleixner
2021-03-17 18:12 ` [PATCH v4 8/9] kentry: Check that syscall entries and syscall exits match Andy Lutomirski
2021-03-17 18:12 ` [PATCH v4 9/9] kentry: Verify kentry state in instrumentation_begin/end() Andy Lutomirski
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=87v99n5dtk.fsf@nanos.tec.linutronix.de \
--to=tglx@linutronix.de \
--cc=brgerst@gmail.com \
--cc=jpoimboe@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mark.rutland@arm.com \
--cc=x86@kernel.org \
/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).