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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1128BC433FE for ; Sat, 22 Oct 2022 06:24:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1A7338E0002; Sat, 22 Oct 2022 02:24:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 157F18E0001; Sat, 22 Oct 2022 02:24:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 01F1E8E0002; Sat, 22 Oct 2022 02:24:09 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id E6D2D8E0001 for ; Sat, 22 Oct 2022 02:24:09 -0400 (EDT) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 9FDBD120204 for ; Sat, 22 Oct 2022 06:24:09 +0000 (UTC) X-FDA: 80047595418.25.ACA9728 Received: from mail-lf1-f43.google.com (mail-lf1-f43.google.com [209.85.167.43]) by imf29.hostedemail.com (Postfix) with ESMTP id 3830B120015 for ; Sat, 22 Oct 2022 06:24:07 +0000 (UTC) Received: by mail-lf1-f43.google.com with SMTP id p8so8595673lfu.11 for ; Fri, 21 Oct 2022 23:24:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:references:in-reply-to :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=Q3DG5ojxl17Jx3b6LFi8HNNnUkTD/weGMM5iXG8GMb4=; b=ArxARJFVuoVE+iD/fesTfpO7v2JXNqmiVwncYu/T8Yaha4e9Xkptb8xqtYmz6hHqRS nyijsu7bQEeezQWccJe/eHXXfOrRdxJmUBWNusYlwDcaDl1tWUzonuhmrWpOliF06EIJ GwpQBfH5D4g8x96tYZOPNHKh2yBpF1o6VErmIW7Wwua9B55oBfgzCrG+YJbtqhg7Lqjl hjVcThyFzimOv16DDLWjJ0xL9ks4tJDzEXBf4V97s47S0DXm4QtTHVYyLNouZAJRmikw U7gyFYxdxcqKWs7EY7z9UBHuIpgIgG5+t1M5b01WXqs9i+KdXIKDD9p/T0gRtZT4Qykb +JOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:references:in-reply-to :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Q3DG5ojxl17Jx3b6LFi8HNNnUkTD/weGMM5iXG8GMb4=; b=0Iwn1dx6QbWmFFf2ugGZXLB+Hwo+BwihOnYzlaqDFXikI2PZrnAvxTg9Q7Izujiaet zDNcehaJnVVND/qjjPRfG5RSin+p2NxW2j5OPAT5LRw96adp/yd31vqSShyPjhj+e8Xw bG7A0IZMVmkJgIsax3yzJLqbdijLElemod6ddds76eyL3hwOntk/IdOocfyT97qwJW96 D0+KLNK38F8blOzYtqCpJj+eucD07rt/EqhsR245uHI08ToeAMZmtZvyCuSPoNlR7YxE jC3QCr2hUgv7Mc5X7AL9/EjjPKF7vlvAnphjvkg9p4ifVlHsjNEMtolR9hdjX3HeApTg ikpw== X-Gm-Message-State: ACrzQf0DP2rllr0NMLprencdBvo09tl8DAiuZ4SDuQqEztJETwhCUDhV zAOh5jNhs3BaVC0cqMtAdTDhLiG1KTfrmWY8IB0= X-Google-Smtp-Source: AMsMyM4SGLSVHu74dsMs8vTf3aI2BSTZ4xR6qP3Ex7SHc9C12m6OkOlrqv5yJI0OUGGcpgKXM4QEJf0eqtUxhQnmqqY= X-Received: by 2002:a19:7414:0:b0:4a2:260e:6408 with SMTP id v20-20020a197414000000b004a2260e6408mr7905720lfe.366.1666419846130; Fri, 21 Oct 2022 23:24:06 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:ab3:5411:0:b0:1f6:575a:5fb7 with HTTP; Fri, 21 Oct 2022 23:24:05 -0700 (PDT) In-Reply-To: References: <20220915150417.722975-19-glider@google.com> <20221019173620.10167-1-youling257@gmail.com> From: youling 257 Date: Sat, 22 Oct 2022 14:24:05 +0800 Message-ID: Subject: Re: [PATCH v7 18/43] instrumented.h: add KMSAN support To: Alexander Potapenko Cc: Marco Elver , Alexander Viro , Alexei Starovoitov , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Biggers , Eric Dumazet , Greg Kroah-Hartman , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jens Axboe , Joonsoo Kim , Kees Cook , Mark Rutland , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Peter Zijlstra , Petr Mladek , Stephen Rothwell , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" ARC-Authentication-Results: i=1; imf29.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=ArxARJFV; spf=pass (imf29.hostedemail.com: domain of youling257@gmail.com designates 209.85.167.43 as permitted sender) smtp.mailfrom=youling257@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666419848; a=rsa-sha256; cv=none; b=zIYqfYWVpKHo4hm7h8wDyEAhf/FZ5G2g9DTUNZN9D47LGEHEMDp/w4gLzb0Xo/M99uo9yM MImA1W01zAO269ydWrI7+4cIjqjLbZRDlVm/WJaHnXAAdLURNG3TUH/8dMFb0suOL7HTT0 2+3sIVAP57UXYr5jFxzyCA4jQNXuSbs= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666419848; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Q3DG5ojxl17Jx3b6LFi8HNNnUkTD/weGMM5iXG8GMb4=; b=L1xVWje5teu9i27MrNLLHZw8Aug8pranv81xaAjlns6MzI/Fr7XCZOjhtgW8OkT3ujFZiI YfbnhjU+SasDPyW8Tthpc49yD/xPmX4bKhd6KHul2+L8ovp0S7JlFf5PGbKI1VnL6n562z O31laY/HCnI3J+TgZpY4y/Uqr0BNYY8= Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=ArxARJFV; spf=pass (imf29.hostedemail.com: domain of youling257@gmail.com designates 209.85.167.43 as permitted sender) smtp.mailfrom=youling257@gmail.com; dmarc=pass (policy=none) header.from=gmail.com X-Stat-Signature: 77n6sxs8keezkjo19x1prnzi61oyjwqa X-Rspamd-Queue-Id: 3830B120015 X-Rspamd-Server: rspam02 X-Rspam-User: X-HE-Tag: 1666419847-766678 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: I test this patch fix my problem. 2022-10-22 4:37 GMT+08:00, Alexander Potapenko : > On Fri, Oct 21, 2022 at 8:19 AM youling 257 wrote: > >> CONFIG_DEBUG_INFO=y >> CONFIG_AS_HAS_NON_CONST_LEB128=y >> # CONFIG_DEBUG_INFO_NONE is not set >> CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y >> # CONFIG_DEBUG_INFO_DWARF4 is not set >> # CONFIG_DEBUG_INFO_DWARF5 is not set >> # CONFIG_DEBUG_INFO_REDUCED is not set >> # CONFIG_DEBUG_INFO_COMPRESSED is not set >> # CONFIG_DEBUG_INFO_SPLIT is not set >> # CONFIG_DEBUG_INFO_BTF is not set >> # CONFIG_GDB_SCRIPTS is not set >> >> perf top still no function name. >> >> 12.90% [kernel] [k] 0xffffffff833dfa64 >> > > I think I know what's going on. The two functions that differ with and > without the patch were passing an incremented pointer to unsafe_put_user(), > which is a macro, e.g.: > > unsafe_put_user((compat_ulong_t)m, umask++, Efault); > > Because that macro didn't evaluate its second parameter, "umask++" was > passed to a call to kmsan_copy_to_user(), which resulted in an extra > increment of umask. > This probably violated some expectations of the userspace app, which in > turn led to repetitive kernel calls. > > Could you please check if the patch below fixes the problem for you? > > diff --git a/arch/x86/include/asm/uaccess.h > b/arch/x86/include/asm/uaccess.h > index 8bc614cfe21b9..1cc756eafa447 100644 > --- a/arch/x86/include/asm/uaccess.h > +++ b/arch/x86/include/asm/uaccess.h > @@ -254,24 +254,25 @@ extern void __put_user_nocheck_8(void); > #define __put_user_size(x, ptr, size, label) \ > do { \ > __typeof__(*(ptr)) __x = (x); /* eval x once */ \ > - __chk_user_ptr(ptr); \ > + __typeof__(ptr) __ptr = (ptr); /* eval ptr once */ \ > + __chk_user_ptr(__ptr); \ > switch (size) { \ > case 1: \ > - __put_user_goto(__x, ptr, "b", "iq", label); \ > + __put_user_goto(__x, __ptr, "b", "iq", label); \ > break; \ > case 2: \ > - __put_user_goto(__x, ptr, "w", "ir", label); \ > + __put_user_goto(__x, __ptr, "w", "ir", label); \ > break; \ > case 4: \ > - __put_user_goto(__x, ptr, "l", "ir", label); \ > + __put_user_goto(__x, __ptr, "l", "ir", label); \ > break; \ > case 8: \ > - __put_user_goto_u64(__x, ptr, label); \ > + __put_user_goto_u64(__x, __ptr, label); \ > break; \ > default: \ > __put_user_bad(); \ > } \ > - instrument_put_user(__x, ptr, size); \ > + instrument_put_user(__x, __ptr, size); \ > } while (0) > > #ifdef CONFIG_CC_HAS_ASM_GOTO_OUTPUT >