From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from canpmsgout11.his.huawei.com (canpmsgout11.his.huawei.com [113.46.200.226]) (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 36806434E30 for ; Tue, 21 Jul 2026 09:27:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.226 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784626038; cv=none; b=TS9FP+E3vUrFhLa4id8HhHf1hsMVBaKBfjPm6bQIcf0fHEHnf8LTQqNzY7l8aSebbwrw118rrEvHy0S3jKz/DrOkET+cwKrJ2zFMn5LilF/fFERXOfvDdPxhUCedRmStZIJV6C+Z5vBlg02J62viMX0a2CmrcwpLr+7+b4XY7sE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784626038; c=relaxed/simple; bh=Bqz9Qi3QfRt4B2c9QY/Qm/zdQGB+jtJFArbLlMXlaGc=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=oHpX+cZlPqkrYi7YtiDK8CwaIxn1BzAfZEqcoDXgbsBfHKLH8QXlRtfSQ7aoni/cmwkYwulNqEz1Qrkr61QIbDVcwn2suepoBgQJi1n8jmCK/CVjCLJ4OovFvjyFba4d27zETZRzwcZg/khm+VTjiYOJlAPbWKH1YBrD9QH6AHw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=jIxiaBiE; arc=none smtp.client-ip=113.46.200.226 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="jIxiaBiE" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=1c85gg17qOp2jVI8fhxIGgJrpPOSpSPj68RXsM9YqFQ=; b=jIxiaBiEZUASBc8flQ1I2Kxi2AQjwRTVk+7jv2wnMBVzpgVwbrHH1P9sWOOXoQKOmfpGn8nRR X2lgXtHd1WrGwtiMFog4QqUZi/Gc3IoY1fNRbmS+gCErqIfBa0tXGkgqtll21JVbEXAywqIb9Kn rsA7SAzkcvjTsgPhf9LV8vA= Received: from mail.maildlp.com (unknown [172.19.162.92]) by canpmsgout11.his.huawei.com (SkyGuard) with ESMTPS id 4h4BcQ1ZvRzKmWF; Tue, 21 Jul 2026 17:17:42 +0800 (CST) Received: from dggpemf500011.china.huawei.com (unknown [7.185.36.131]) by mail.maildlp.com (Postfix) with ESMTPS id BE91A40586; Tue, 21 Jul 2026 17:27:06 +0800 (CST) Received: from [10.67.109.254] (10.67.109.254) by dggpemf500011.china.huawei.com (7.185.36.131) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Tue, 21 Jul 2026 17:27:05 +0800 Message-ID: <4b6d760a-8270-443b-878f-37d46d9bed47@huawei.com> Date: Tue, 21 Jul 2026 17:27:04 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v17 15/15] arm64: vdso: Expose sigreturn address on vdso to the kernel To: Linus Walleij CC: , , , , , , , , , , , , , , , , , , , , , References: <20260721081858.1169276-1-ruanjinjie@huawei.com> <20260721081858.1169276-16-ruanjinjie@huawei.com> From: Jinjie Ruan In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-ClientProxiedBy: kwepems200002.china.huawei.com (7.221.188.68) To dggpemf500011.china.huawei.com (7.185.36.131) On 7/21/2026 4:55 PM, Linus Walleij wrote: > On Tue, Jul 21, 2026 at 10:19 AM Jinjie Ruan wrote: > >> Syscall User Dispatch (SUD) must not intercept the signal trampoline >> code, otherwise returning from a signal with a locked selector may >> cause infinite recursion into the signal handler. >> >> Provide an arm64 implementation of arch_syscall_is_vdso_sigreturn() >> to exclude these sigreturn syscalls from dispatch. >> >> For native 64-bit tasks, check whether the current PC matches the 'svc #0' >> instruction inside the vDSO sigreturn trampoline (defined in >> arch/arm64/kernel/vdso/sigreturn.S as below). >> >> SYM_CODE_START(__kernel_rt_sigreturn) >> mov x8, #__NR_rt_sigreturn >> svc #0 >> SYM_CODE_END(__kernel_rt_sigreturn) >> >> For COMPAT tasks, verify that the instruction falls within the dedicated >> 'sigpage' range, since compat signal handlers use this architecture- >> specific page (not the vDSO) for their return trampoline. This prevents >> SUD from incorrectly dispatching syscalls issued during signal return. >> >> Suggested-by: Thomas Weißschuh >> Suggested-by: Kevin Brodsky >> Suggested-by: kemal >> Signed-off-by: Jinjie Ruan > > I'm a bit scared about SUD. > > Certainly we can merge patches 1-14 first and iron out > any trouble related to that and split this off so a separate > series to be applied lated? Yes, Mark's idea is the same. We can place the SUD patch here separately and wait for thorough testing and review. Link: https://lore.kernel.org/all/akZgV0Y4YAmB43_g@J2N7QTR9R3.cambridge.arm.com/ > > Yours, > Linus Walleij