From: Josh Poimboeuf <jpoimboe@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: x86@kernel.org, linux-kernel@vger.kernel.org,
Miroslav Benes <mbenes@suse.cz>
Subject: Re: [PATCH 3/3] objtool: Generate ORC data for __pfx code
Date: Thu, 13 Apr 2023 08:29:33 -0700 [thread overview]
Message-ID: <20230413152933.cxhmocvbdlucvizx@treble> (raw)
In-Reply-To: <20230413112426.GM4253@hirez.programming.kicks-ass.net>
On Thu, Apr 13, 2023 at 01:24:26PM +0200, Peter Zijlstra wrote:
> > + if (!insn->cfi) {
> > + /*
> > + * This can happen if stack validation isn't enabled or the
> > + * function is annotated with STACK_FRAME_NON_STANDARD.
> > + */
> > + return 0;
> > + }
> > +
> > + /* Propagate insn->cfi to the prefix code */
> > + cfi = cfi_hash_find_or_add(insn->cfi);
> > + for (; prev != insn; prev = next_insn_same_sec(file, prev))
> > + prev->cfi = cfi;
> > +
> > return 0;
> > }
>
> FWIW, this makes the whole thing hard rely on the prefix being single
> byte NOPs -- which they are, but perhaps we should assert this?
Couldn't they be any stack-invariant instructions?
--
Josh
next prev parent reply other threads:[~2023-04-13 15:29 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-12 20:26 [PATCH 0/3] " Josh Poimboeuf
2023-04-12 20:26 ` [PATCH 1/3] objtool: Separate prefix code from stack validation code Josh Poimboeuf
2023-04-13 9:30 ` Peter Zijlstra
2023-04-13 15:27 ` Josh Poimboeuf
2023-04-14 14:47 ` [tip: objtool/core] " tip-bot2 for Josh Poimboeuf
2023-04-12 20:26 ` [PATCH 2/3] x86/linkage: Fix padding for typed functions Josh Poimboeuf
2023-04-14 14:47 ` [tip: objtool/core] " tip-bot2 for Josh Poimboeuf
2023-04-12 20:26 ` [PATCH 3/3] objtool: Generate ORC data for __pfx code Josh Poimboeuf
2023-04-13 11:23 ` Peter Zijlstra
2023-04-13 11:24 ` Peter Zijlstra
2023-04-13 15:29 ` Josh Poimboeuf [this message]
2023-04-13 19:24 ` Peter Zijlstra
2023-04-13 19:30 ` Josh Poimboeuf
2023-04-14 14:47 ` [tip: objtool/core] " tip-bot2 for Josh Poimboeuf
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