From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1EC2C3D74 for ; Mon, 21 Nov 2022 12:44:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70C55C43154; Mon, 21 Nov 2022 12:44:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669034654; bh=jP04T/lJFie4UVeQ6Tgo+/+ggQt1F+AacHioAT82LX4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QnhSA9ydmb2Y5WgHN3MfdPV+5eHT+RW+j4QtHG/4LZ3peI0A7HMMazgwCAhNS9r1f AxXK7Q/m/7vSSRJ0Qe4BKCPaLPdRO21HCPXMI7sF8P8wcGuL0PxViMXDvGpAKYH+Ej q5+YJtmQ+np+JldndHAQ9qBwpBdmgpOFa66ndzn4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Peter Zijlstra (Intel)" , Borislav Petkov , Thadeu Lima de Souza Cascardo , Suleiman Souhlal Subject: [PATCH 4.19 12/34] x86/entry: Remove skip_r11rcx Date: Mon, 21 Nov 2022 13:43:34 +0100 Message-Id: <20221121124151.322081950@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221121124150.886779344@linuxfoundation.org> References: <20221121124150.886779344@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Peter Zijlstra commit 1b331eeea7b8676fc5dbdf80d0a07e41be226177 upstream. Yes, r11 and rcx have been restored previously, but since they're being popped anyway (into rsi) might as well pop them into their own regs -- setting them to the value they already are. Less magical code. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20220506121631.365070674@infradead.org Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Suleiman Souhlal Signed-off-by: Greg Kroah-Hartman --- arch/x86/entry/calling.h | 10 +--------- arch/x86/entry/entry_64.S | 3 +-- 2 files changed, 2 insertions(+), 11 deletions(-) --- a/arch/x86/entry/calling.h +++ b/arch/x86/entry/calling.h @@ -146,27 +146,19 @@ For 32-bit we have the following convent .endm -.macro POP_REGS pop_rdi=1 skip_r11rcx=0 +.macro POP_REGS pop_rdi=1 popq %r15 popq %r14 popq %r13 popq %r12 popq %rbp popq %rbx - .if \skip_r11rcx - popq %rsi - .else popq %r11 - .endif popq %r10 popq %r9 popq %r8 popq %rax - .if \skip_r11rcx - popq %rsi - .else popq %rcx - .endif popq %rdx popq %rsi .if \pop_rdi --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -311,8 +311,7 @@ GLOBAL(entry_SYSCALL_64_after_hwframe) * perf profiles. Nothing jumps here. */ syscall_return_via_sysret: - /* rcx and r11 are already restored (see code above) */ - POP_REGS pop_rdi=0 skip_r11rcx=1 + POP_REGS pop_rdi=0 /* * Now all regs are restored except RSP and RDI.