linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: x86@kernel.org, jpoimboe@redhat.com, jgross@suse.com, mbenes@suze.cz
Cc: linux-kernel@vger.kernel.org, peterz@infradead.org
Subject: [PATCH 8/9] objtool: Skip magical retpoline .altinstr_replacement
Date: Fri, 12 Mar 2021 18:16:21 +0100	[thread overview]
Message-ID: <20210312171653.832063970@infradead.org> (raw)
In-Reply-To: 20210312171613.533405394@infradead.org

When the .altinstr_replacement is a retpoline, skip the alternative.
We already special case retpolines anyway.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
 tools/objtool/special.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

--- a/tools/objtool/special.c
+++ b/tools/objtool/special.c
@@ -106,6 +106,14 @@ static int get_alt_entry(struct elf *elf
 			return -1;
 		}
 
+		/*
+		 * Skip retpoline .altinstr_replacement... we already rewrite the
+		 * instructions for retpolines anyway, see arch_is_retpoline()
+		 * usage in add_{call,jump}_destinations().
+		 */
+		if (arch_is_retpoline(new_reloc->sym))
+			return 1;
+
 		alt->new_sec = new_reloc->sym->sec;
 		alt->new_off = (unsigned int)new_reloc->addend;
 
@@ -154,7 +162,9 @@ int special_get_alts(struct elf *elf, st
 			memset(alt, 0, sizeof(*alt));
 
 			ret = get_alt_entry(elf, entry, sec, idx, alt);
-			if (ret)
+			if (ret > 0)
+				continue;
+			if (ret < 0)
 				return ret;
 
 			list_add_tail(&alt->list, alts);



  parent reply	other threads:[~2021-03-12 17:18 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-12 17:16 [PATCH 0/9] x86,objtool: Optimize !RETPOLINE Peter Zijlstra
2021-03-12 17:16 ` [PATCH 1/9] x86/retpoline: Simplify retpolines Peter Zijlstra
2021-03-12 17:16 ` [PATCH 2/9] objtool: Correctly handle retpoline thunk calls Peter Zijlstra
2021-03-16 21:19   ` Josh Poimboeuf
2021-03-12 17:16 ` [PATCH 3/9] objtool: Per arch retpoline naming Peter Zijlstra
2021-03-12 17:16 ` [PATCH 4/9] objtool: Fix static_call list generation Peter Zijlstra
2021-03-17  3:18   ` Josh Poimboeuf
2021-03-12 17:16 ` [PATCH 5/9] objtool: Rework rebuild_reloc logic Peter Zijlstra
2021-03-17  3:34   ` Josh Poimboeuf
2021-03-17  8:12     ` Peter Zijlstra
2021-03-18  0:49       ` Josh Poimboeuf
2021-03-18 12:57         ` Peter Zijlstra
2021-03-18 16:36           ` Josh Poimboeuf
2021-03-18 17:04             ` Peter Zijlstra
2021-03-18 17:38               ` Josh Poimboeuf
2021-03-19  0:19                 ` Josh Poimboeuf
2021-03-19  9:22                 ` Peter Zijlstra
2021-03-19 15:15                   ` Josh Poimboeuf
2021-03-12 17:16 ` [PATCH 6/9] objtool: Add elf_create_undef_symbol() Peter Zijlstra
2021-03-17 13:52   ` Miroslav Benes
2021-03-17 14:13     ` Peter Zijlstra
2021-03-17 14:39       ` Miroslav Benes
2021-03-17 15:08         ` Sami Tolvanen
2021-03-18  0:46       ` Josh Poimboeuf
2021-03-18  7:56         ` Peter Zijlstra
2021-03-12 17:16 ` [PATCH 7/9] objtool: Allow archs to rewrite retpolines Peter Zijlstra
2021-03-12 17:16 ` Peter Zijlstra [this message]
2021-03-12 17:16 ` [PATCH 9/9] objtool,x86: Rewrite retpoline thunk calls Peter Zijlstra

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=20210312171653.832063970@infradead.org \
    --to=peterz@infradead.org \
    --cc=jgross@suse.com \
    --cc=jpoimboe@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mbenes@suze.cz \
    --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).