From: Oleg Nesterov <oleg@redhat.com>
To: Jiri Olsa <olsajiri@gmail.com>
Cc: Deepak Gupta <debug@rivosinc.com>,
"Edgecombe, Rick P" <rick.p.edgecombe@intel.com>,
"songliubraving@fb.com" <songliubraving@fb.com>,
"luto@kernel.org" <luto@kernel.org>,
"mhiramat@kernel.org" <mhiramat@kernel.org>,
"andrii@kernel.org" <andrii@kernel.org>,
"john.fastabend@gmail.com" <john.fastabend@gmail.com>,
"linux-api@vger.kernel.org" <linux-api@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"mingo@redhat.com" <mingo@redhat.com>,
"rostedt@goodmis.org" <rostedt@goodmis.org>,
"ast@kernel.org" <ast@kernel.org>,
"tglx@linutronix.de" <tglx@linutronix.de>,
"linux-man@vger.kernel.org" <linux-man@vger.kernel.org>,
"yhs@fb.com" <yhs@fb.com>,
"daniel@iogearbox.net" <daniel@iogearbox.net>,
"peterz@infradead.org" <peterz@infradead.org>,
"linux-trace-kernel@vger.kernel.org"
<linux-trace-kernel@vger.kernel.org>,
"bp@alien8.de" <bp@alien8.de>,
"bpf@vger.kernel.org" <bpf@vger.kernel.org>,
"x86@kernel.org" <x86@kernel.org>
Subject: Re: [PATCHv5 bpf-next 6/8] x86/shstk: Add return uprobe support
Date: Wed, 15 May 2024 17:26:09 +0200 [thread overview]
Message-ID: <20240515152609.GD6821@redhat.com> (raw)
In-Reply-To: <ZkTIU1QUAJF0f0KK@krava>
On 05/15, Jiri Olsa wrote:
>
> On Wed, May 15, 2024 at 01:19:20PM +0200, Oleg Nesterov wrote:
> > Let me ask a couple of really stupid questions. What if the shadow stack
> > is "shorter" than the normal stack? I mean,
> >
> > enable_shstk()
> > {
> > prctl(ARCH_SHSTK_SHSTK);
I meant ARCH_SHSTK_ENABLE, of course
> > }
> >
> > what happens when enable_shstk() returns?
>
> I think it will crash, there's explanation in the comment in
> tools/testing/selftests/x86/test_shadow_stack.c test
OK, thanks...
But test_shadow_stack.c doesn't do ARCH_PRCTL(ARCH_SHSTK_DISABLE) if
all the tests succeed ? Confused but nevermind.
> > And what is the purpose of fpregs_lock_and_load() ? Why do we need to
> > fpregs_restore_userregs() in shstk_setup() and other places?
> >
> > Oleg.
> >
>
next prev parent reply other threads:[~2024-05-15 15:28 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-07 10:53 [PATCHv5 bpf-next 0/8] uprobe: uretprobe speed up Jiri Olsa
2024-05-07 10:53 ` [PATCHv5 bpf-next 1/8] uprobe: Wire up uretprobe system call Jiri Olsa
2024-05-07 10:53 ` [PATCHv5 bpf-next 2/8] uprobe: Add uretprobe syscall to speed up return probe Jiri Olsa
2024-05-07 10:53 ` [PATCHv5 bpf-next 3/8] selftests/bpf: Add uretprobe syscall test for regs integrity Jiri Olsa
2024-05-07 10:53 ` [PATCHv5 bpf-next 4/8] selftests/bpf: Add uretprobe syscall test for regs changes Jiri Olsa
2024-05-07 10:53 ` [PATCHv5 bpf-next 5/8] selftests/bpf: Add uretprobe syscall call from user space test Jiri Olsa
2024-05-07 16:57 ` Andrii Nakryiko
2024-05-07 10:53 ` [PATCHv5 bpf-next 6/8] x86/shstk: Add return uprobe support Jiri Olsa
2024-05-07 17:35 ` Edgecombe, Rick P
2024-05-09 8:30 ` Jiri Olsa
2024-05-09 16:24 ` Edgecombe, Rick P
2024-05-11 21:09 ` Jiri Olsa
2024-05-13 9:50 ` Masami Hiramatsu
2024-05-13 17:12 ` Edgecombe, Rick P
2024-05-13 21:23 ` Jiri Olsa
2024-05-15 1:10 ` Edgecombe, Rick P
2024-05-15 1:44 ` Deepak Gupta
2024-05-15 11:19 ` Oleg Nesterov
2024-05-15 14:36 ` Jiri Olsa
2024-05-15 15:18 ` Edgecombe, Rick P
2024-05-15 15:26 ` Oleg Nesterov [this message]
2024-05-15 15:31 ` Edgecombe, Rick P
2024-05-15 11:35 ` Oleg Nesterov
2024-05-15 15:13 ` Edgecombe, Rick P
2024-05-15 15:42 ` Oleg Nesterov
2024-05-19 22:18 ` Jiri Olsa
2024-05-21 1:31 ` Edgecombe, Rick P
2024-05-21 10:11 ` Jiri Olsa
2024-05-07 10:53 ` [PATCHv5 bpf-next 7/8] selftests/x86: Add return uprobe shadow stack test Jiri Olsa
2024-05-13 9:45 ` Masami Hiramatsu
2024-05-13 21:28 ` Jiri Olsa
2024-05-07 10:53 ` [PATCHv5 8/8] man2: Add uretprobe syscall page Jiri Olsa
2024-05-07 11:13 ` Dmitry V. Levin
2024-05-07 11:49 ` Jiri Olsa
2024-05-07 13:44 ` Alejandro Colomar
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=20240515152609.GD6821@redhat.com \
--to=oleg@redhat.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bp@alien8.de \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=debug@rivosinc.com \
--cc=john.fastabend@gmail.com \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-man@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mhiramat@kernel.org \
--cc=mingo@redhat.com \
--cc=olsajiri@gmail.com \
--cc=peterz@infradead.org \
--cc=rick.p.edgecombe@intel.com \
--cc=rostedt@goodmis.org \
--cc=songliubraving@fb.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
--cc=yhs@fb.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 read-only IMAP folder(s) and NNTP newsgroup(s).