From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2E254CA101F for ; Wed, 10 Sep 2025 11:59:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:MIME-Version: Content-Transfer-Encoding:Content-Type:References:In-Reply-To:Date:Cc:To:From :Subject:Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=OySP/ewzDP7qYoXqik2jfMmlTSWEYVQiB3tXcLsIXio=; b=kXmjzqsyZvWFu7m8qfI4WeNBMU o44AAo20/8zTPK8jAccBidL7RcZYlfGF+uyBt0tcu5OyqMyUYlCsWDufRpPAMA5YHVLFaR/f5CJd0 vdD8JJ1No0gHqU7J4Xmonw2HXmVLpvK6n0fWPFcuA592vkm4pEKfHldJ9VDqA3v8F1x5M4a2//eWd GRCgfHJ1VFdtqetEEgRb24ev18HCOULDpqRVaFSWpX1z3X/R7MeeZGf5Z4sjWbTTVlxSC3WAuqwzy wulBw/YO+1SuPXqYgF/90IiRFURgoifR4aJDVDWZaDIQ3YIB8HrAZ+3hNb2MhUsgY4jqcyRnG3BpX VG5ojXfA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uwJTh-0000000Dy8E-411i; Wed, 10 Sep 2025 11:59:09 +0000 Received: from s3.sipsolutions.net ([2a01:4f8:242:246e::2] helo=sipsolutions.net) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uwJTf-0000000Dy73-2Crj for linux-um@lists.infradead.org; Wed, 10 Sep 2025 11:59:08 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=MIME-Version:Content-Transfer-Encoding: Content-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=OySP/ewzDP7qYoXqik2jfMmlTSWEYVQiB3tXcLsIXio=; t=1757505547; x=1758715147; b=lohfoZSR0E/cvjVs+86QQUM+ablrzplu7gs5A4fMRVqRVZC +Ti9lCwfeMuYCw9dcWHM8pushVsCYEPFQry7lu6gcEKzcVx4d6kahZxX1gWpFwDIoj4ZXHDKypNbY PYWiK/mdZn8dxpDPs0yuoWIU99ujxLaU+UsAzUx/eL4LDdnaMZHYIRcxJ0dU1xJY/cHGyksZc7plx r/x1wZawKn63fBV3trJZ/cwIPZUdMVGABS23kpQKidC3SZ2h+KoaC6VzXnGH1NxjbAxiWvNxbXvyr pZNFmbqdJmCdj25ONUSU70E6ipNEA0Tvz3BQAHR0EyzLdBQolnXiuaMzHIzpbIrg==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.98.2) (envelope-from ) id 1uwJTb-0000000CnNR-07Z6; Wed, 10 Sep 2025 13:59:03 +0200 Message-ID: Subject: Re: [PATCH v2 03/10] um: vdso: Implement __vdso_getcpu() via syscall From: Johannes Berg To: Tiwei Bie , richard@nod.at, anton.ivanov@cambridgegreys.com Cc: linux-um@lists.infradead.org, linux-kernel@vger.kernel.org, benjamin@sipsolutions.net, arnd@arndb.de, tiwei.btw@antgroup.com Date: Wed, 10 Sep 2025 13:59:02 +0200 In-Reply-To: <20250810055136.897712-4-tiwei.bie@linux.dev> (sfid-20250810_075310_514820_7C2543B7) References: <20250810055136.897712-1-tiwei.bie@linux.dev> <20250810055136.897712-4-tiwei.bie@linux.dev> (sfid-20250810_075310_514820_7C2543B7) Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) MIME-Version: 1.0 X-malware-bazaar: not-scanned X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250910_045907_560481_659B065A X-CRM114-Status: UNSURE ( 8.16 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org On Sun, 2025-08-10 at 13:51 +0800, Tiwei Bie wrote: > From: Tiwei Bie >=20 > We are going to support SMP in UML, so we can not hard code > the CPU and NUMA node in __vdso_getcpu() anymore. Correct. But does that mean we actually have to implement it via syscall in the VDSO? That seems a bit odd? ARM doesn't seem to have getcpu in the VDSO at all, for example, so could we do the same and just remove it? johannes