From nobody Wed Jan 22 19:48:08 2025 X-Original-To: fs@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4YdZPP0drNz5kyJh for ; Wed, 22 Jan 2025 19:48:09 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R11" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4YdZPP07kFz487D for ; Wed, 22 Jan 2025 19:48:09 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1737575289; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/dzjZgrp8yzcORSH+pn5eoehi1VSn4OORfdhmSU61F0=; b=bAdk6cpxT1f5yWijeN1v9dFswztn9tEZTm1+AChSA78Syn4CI8ERCweFdXaCcEs+g7Xq2U WsdKRzZBHpq6VZVEG1udQDgdEvn/BruThMQJVcHiark+jfM/zZ8r6mBu3vG9NOZqk+0FhV 5qmofvRSiSoXTEy7+Nf5UfdiuSo6nq2q+lYUxPPhMbi/iTOGjGxwBKWzlD5795gx8G5PBW 2QrASiX6OQJE3VvlWMhAPbBGBqRjBDu2wlQux7drryj0f6nLZRBV7/GL3UqJoZfIflwxUg mLZIJV/tcxTn+SPpLPLmNo8bFc2e2hcYLabGBlZDN98DPIh6hf4yvWZDh9GdiQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1737575289; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/dzjZgrp8yzcORSH+pn5eoehi1VSn4OORfdhmSU61F0=; b=R7XfPcQPXmsL2bk7FJYrAh2ok/rTfgtmwqOrukObPX4AyVDcvWaKx0CxggUmNxMWKVVI+n BwKejgDqWf05GWoMPW6lhueinWiksr188XVc7Mm2JmBIX6a80P8hckTw2TOdFz4mdP45BH cpZvaKeWVUz7Dzeg6cJ9bgH3OkaROkOp9vNC5DhRcYWxGwyXd1YP8Y1qPc1CUKqQJFvlEf tCtEwnm7eO8VLiiEqyNz9uFRxUBBrgHvEqpv+h1gf+3joZGV8j7nR9fqZyJvP2e8+uLy8a yhih3LZJt4yBILlsmcQWYUlOHHaVBnfeUEDaObwAxaEZUlBXKm4POfzqoEuRXw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1737575289; a=rsa-sha256; cv=none; b=xkDkCXfb2bj0wV0md9z4qeRLsm6UDOAhI2BG5V2xnlWRn08kJsKivKSy4khBxhmNdFZS/j sSOL97b+pJUSGgKb8CxQ4QKiYFzCoYxuNmOSDoZQcTPXUqPL8DGUnoWT+XAA4VUJwxe4sD XZTR47oaB4un5SCa7jzUeakauEPe3OU+gulEZq7fstNa6SV+blapo/UDwI5GjBcGHTlB0D tGvHFAphfsrPFGuO4rQeKjSPoWcxQL38Ad/GrypKmrxYerzKhqjdju8Uys26xaz49UAGa0 gaL6nTUtO/eBXc/BvlgIHJOq4enbGHXTz804Ycf3VpwDB+pR2graJBwP7uv5cQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4YdZPN6Sv5z167d for ; Wed, 22 Jan 2025 19:48:08 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 50MJm8a4045745 for ; Wed, 22 Jan 2025 19:48:08 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 50MJm8sV045744 for fs@FreeBSD.org; Wed, 22 Jan 2025 19:48:08 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: fs@FreeBSD.org Subject: [Bug 281402] zfs: kmsan reports Uninitialized UMA memory from zio_data_buf_alloc Date: Wed, 22 Jan 2025 19:48:08 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: asomers@FreeBSD.org X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: fs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="UTF-8" X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Filesystems List-Archive: https://lists.freebsd.org/archives/freebsd-fs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-fs@FreeBSD.org MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D281402 --- Comment #5 from Alan Somers --- I've determined the cause of the alerts, and it's boring: SIMD code. When I change the raidz implementation to the scalar algorithm, all of the KMSAN alerts go away. But with any SIMD algorithm, I get the alerts. Here's a summary of the various raidz algorithms.=20=20 - cycle: warnings - fastest: warnings - original: ok - scaler: ok - sse2: warnings - ssse3: warnings - avx2: warnings - avx512f: untested - avx512bw: untested I'll open a separate PR to OpenZFS to make the algorithm easier to select.= =20 Regarding the false alarms, if KMSAN can't be made to understand SIMD instructions, would it be possible to annotate functions like raidz_gen_pq_= add with extra information for KMSAN? --=20 You are receiving this mail because: You are the assignee for the bug.=