From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D99A8481257; Tue, 5 May 2026 14:50:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777992615; cv=none; b=cFocj9PmYfF/M/YsQR62LGPSvqe3gvU70zOxRx+ehZWydQ2cV/zQkOz5XEjxVH2HbNQGvekFS95PQ61PAxNdRvdhI7hZhojgUWjRhN6exCHFRdlBXWGyhvqbjimislsrrHK1kS/DlAVUpcbtWOhr/O7JO63xyTTPu2GqeYfLw7M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777992615; c=relaxed/simple; bh=35ASUL/A+SFevDAhCefLpyPRj7qJbSq9Dc0lsV1LTJ8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=N3UHJexIwitLYouQA2YGdb7ZAysZVUKi7noPiBRNWFS2yj5QKg6/1cGvs81hepO3UvXYPj/bSt6JpJUu8geqYpLbyAbhn59cV3+tGt6gRINXdhJvSVZwvmi+7EAU5xAIWcIvih16rWnIyKOn6J33G8TuC5VrHUsaOQqysg70cRY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=OWRI0ab3; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OWRI0ab3" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=MhIH6P4L9AHrtbUCk5z0gOsY/j0PxcVoR9jw1AI5Xkg=; b=OWRI0ab3sH+PmXYQl/+8rjjdTj 4peTJVZ4lPgPFSxwUZUebGE+gGchVIwHFCAWM+NVUUYa0X5DrAfOvRR0kGEE9gIiJQJXB4yKPOcrP M26jeunhYfFt2kxxfDCxMNuTgkEuAuR7vsp6aR2ofat3cpWODaNqyFSJfi/4jJ1j5ZXW34JNjkiKs fTkUdeJiJSIds3AnbocGr0q45oEuUpkBYKEQ20Jit62UHSp8cUMtTQGNEdsnxwT34DMPF5ZhAZfG7 CsEFCOTl5adOzaLxrZE3smVEf+DCsnHtXXLyuJ9Q66Vlg0T6Q1vn/h0f/uVPmhY0Hsu//2zBgYhvt xtSisCIw==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1wKH5q-0000000DoGA-1dyJ; Tue, 05 May 2026 14:49:50 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 1E81B300324; Tue, 05 May 2026 16:49:49 +0200 (CEST) Date: Tue, 5 May 2026 16:49:49 +0200 From: Peter Zijlstra To: Sathvika Vasireddy Cc: nathan@kernel.org, nsc@kernel.org, maddy@linux.ibm.com, mpe@ellerman.id.au, npiggin@gmail.com, chleroy@kernel.org, jpoimboe@kernel.org, ojeda@kernel.org, masahiroy@kernel.org, lossin@kernel.org, tamird@kernel.org, thomas.weissschuh@linutronix.de, rostedt@goodmis.org, ihor.solodrai@linux.dev, thuth@redhat.com, pmladek@suse.com, aliceryhl@google.com, elver@google.com, kees@kernel.org, legion@kernel.org, ardb@kernel.org, yuxuan.zuo@outlook.com, alexghiti@rivosinc.com, alexandre.chartre@oracle.com, bp@alien8.de, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH v1 1/6] objtool/powerpc: Add build-time fixup of alternate feature branch targets Message-ID: <20260505144949.GO3102924@noisy.programming.kicks-ass.net> References: <20260505084628.17940-1-sv@linux.ibm.com> <20260505084628.17940-2-sv@linux.ibm.com> <20260505144539.GX3126523@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260505144539.GX3126523@noisy.programming.kicks-ass.net> On Tue, May 05, 2026 at 04:45:39PM +0200, Peter Zijlstra wrote: > On Tue, May 05, 2026 at 02:16:23PM +0530, Sathvika Vasireddy wrote: > > switch (opcode) { > > + case 16: > > Like case 18 below, this wants a comment describing which instruction > this is; bclr ? Also, isn't that typically used for return, suggesting at least something should have INSN_RETURN on? > > + if (ins & 1) > > + typ = INSN_OTHER; > > + else > > + typ = INSN_JUMP_CONDITIONAL; > > + imm = ins & 0xfffc; > > + if (imm & 0x8000) > > + imm -= 0x10000; > > + insn->immediate = imm | aa; > > + break; > > + > > case 18: /* b[l][a] */ > > if (ins == 0x48000005) /* bl .+4 */ > > typ = INSN_OTHER;