linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Alexandre Chartre <alexandre.chartre@oracle.com>
To: x86@kernel.org
Cc: linux-kernel@vger.kernel.org, jpoimboe@redhat.com,
	peterz@infradead.org, jthierry@redhat.com, tglx@linutronix.de,
	alexandre.chartre@oracle.com
Subject: [PATCH V2 6/9] x86/speculation: Change __FILL_RETURN_BUFFER to work with objtool
Date: Tue,  7 Apr 2020 09:31:39 +0200	[thread overview]
Message-ID: <20200407073142.20659-7-alexandre.chartre@oracle.com> (raw)
In-Reply-To: <20200407073142.20659-1-alexandre.chartre@oracle.com>

Change __FILL_RETURN_BUFFER so that the stack state is deterministically
defined for each iteration and that objtool can have an accurate view
of the stack.

Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com>
---
 arch/x86/include/asm/nospec-branch.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 5c24a7b35166..9a946fd5e824 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -60,8 +60,8 @@
 	jmp	775b;				\
 774:						\
 	dec	reg;				\
-	jnz	771b;				\
-	add	$(BITS_PER_LONG/8) * nr, sp;
+	add	$(BITS_PER_LONG/8) * 2, sp;	\
+	jnz	771b;
 
 #ifdef __ASSEMBLY__
 
-- 
2.18.2


  parent reply	other threads:[~2020-04-07  7:28 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-07  7:31 [PATCH V2 0/9] objtool changes to remove all ANNOTATE_NOSPEC_ALTERNATIVE Alexandre Chartre
2020-04-07  7:31 ` [PATCH V2 1/9] objtool: Introduce HINT_RET_OFFSET Alexandre Chartre
2020-04-07 12:53   ` Peter Zijlstra
2020-04-07 13:17     ` Alexandre Chartre
2020-04-07  7:31 ` [PATCH V2 2/9] objtool: UNWIND_HINT_RET_OFFSET should not check registers Alexandre Chartre
2020-05-01 18:22   ` [tip: objtool/core] " tip-bot2 for Alexandre Chartre
2020-04-07  7:31 ` [PATCH V2 3/9] objtool: is_fentry_call() crashes if call has no destination Alexandre Chartre
2020-04-07  7:31 ` [PATCH V2 4/9] objtool: Allow branches within the same alternative Alexandre Chartre
2020-04-07  7:31 ` [PATCH V2 5/9] objtool: Add support for intra-function calls Alexandre Chartre
2020-04-07 13:07   ` Peter Zijlstra
2020-04-07 13:28     ` Alexandre Chartre
2020-04-08 14:06       ` Alexandre Chartre
2020-04-08 14:19         ` Julien Thierry
2020-04-08 16:03           ` Alexandre Chartre
2020-04-08 16:04             ` Julien Thierry
2020-04-08 17:06               ` Alexandre Chartre
2020-04-08 17:07                 ` Julien Thierry
2020-04-07  7:31 ` Alexandre Chartre [this message]
2020-04-07 13:27   ` [PATCH V2 6/9] x86/speculation: Change __FILL_RETURN_BUFFER to work with objtool Josh Poimboeuf
2020-04-07  7:31 ` [PATCH V2 7/9] x86/speculation: Annotate intra-function calls Alexandre Chartre
2020-04-07  7:31 ` [PATCH V2 8/9] x86/speculation: Add unwind hint to trampoline return Alexandre Chartre
2020-04-07  7:31 ` [PATCH V2 9/9] x86/speculation: Remove all ANNOTATE_NOSPEC_ALTERNATIVE directives Alexandre Chartre
2020-04-07 13:28   ` Peter Zijlstra
2020-04-07 13:34     ` Josh Poimboeuf
2020-04-07 14:32       ` Alexandre Chartre
2020-04-07 16:18         ` Alexandre Chartre
2020-04-07 16:28           ` Josh Poimboeuf
2020-04-07 17:01             ` Alexandre Chartre
2020-04-07 17:26               ` Peter Zijlstra
2020-04-07 17:27             ` Peter Zijlstra
2020-04-08 21:35               ` Peter Zijlstra
2020-04-09  8:18                 ` Alexandre Chartre
2020-04-09 10:34                   ` Peter Zijlstra
2020-04-09 10:40                     ` Peter Zijlstra
2020-04-07 16:41           ` Peter Zijlstra
2020-04-07 17:04             ` Alexandre Chartre
2020-04-07 13:52   ` Peter Zijlstra
2020-04-07 13:59     ` Peter Zijlstra
2020-04-07 13:35 ` [PATCH V2 0/9] objtool changes to remove all ANNOTATE_NOSPEC_ALTERNATIVE Josh Poimboeuf
2020-04-07 14:02   ` Alexandre Chartre

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=20200407073142.20659-7-alexandre.chartre@oracle.com \
    --to=alexandre.chartre@oracle.com \
    --cc=jpoimboe@redhat.com \
    --cc=jthierry@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    --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).