From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=90.155.92.199 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793708840; b=BMJFzZlvqS6ysPN/uwxl12HnhrnVu8icBeA5l+VtwhJnKGk1mGQUwGUikt+r8JICOdiI 5RJNt1HQYfwdPmcfpkD1357HjiaGJTrqe9SIqx0vpDRJmaqY7xFH2VEUAELJ1eh58wC5k jPtvru2eDWQ9+tHj5sOHMYt6OHAMhAXJ8H7oU40zVi6NEeFVlG6OOxjyeI//bcKYMtzi5 I33ocRMRXGwrp+29wE6OeZDCpb6DNTZBjJZH2RJzCY/Ybp53FHM/jNlPlW4vBkoLPTkEj WcwlALo5LOJNtRBvSKM4oNJvzss8jGed/l/N5sx0c3Mc84rSl95FvFUzPYDsT++rXnw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793708840; h=DMARC-Filter:DKIM-Signature:Received:Received:Date:From:To:Cc: Subject:Message-ID:References:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; bh=DyJu+3/AT7hm4iQUNa2fs6Lr4tUQc1qSvYE1x28gUus=; b=DgVuznmCAcvFzxLT/nFmsp9Xql9nKXBIJysD2k16BscuIebYYnvCLQrxXOjqy2+miFRW ElhTxb7lXQyW88WsA5VwC6Pe/eR5Z/kLLu7mYcVHZ7d1mEgrb/t785/q+I2Zt/C2IeyHt R5A41SDrJlcFfcF20wt592lSwP/CAoKP+A5oxm2DTQReSiROq1IFUQ3SbQaRFUTosgtci B/4hZONNJruriH0p/7NSHVqGo+s91t6KbNvrfeCwGetXgvi2t7bzVTNepusFVY7lW7os2 87VccE8f4sWDX/2Pdc10Et5UVL9L1bOCalWmmLRwRlpECBBlYlO8LA/9pYUlM/WxDgA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=infradead.org; spf=pass smtp.mailfrom=infradead.org; dkim=pass header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=desiato.20200630 header.b=Obm3p5tJ; arc=none smtp.remote-ip=90.155.92.199 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B647F606A326; Tue, 3 Nov 2026 12:27:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org B647F606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=infradead.org header.i=@infradead.org header.a=rsa-sha256 header.s=desiato.20200630 header.b=Obm3p5tJ DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=DyJu+3/AT7hm4iQUNa2fs6Lr4tUQc1qSvYE1x28gUus=; b=Obm3p5tJ8cbPtFXgkX+mPa/AcV asrC8ICkIHF/9B3UbCD97jpK2r3DXjYM/y+dIInI1yLRB1TAOOOYAm2F3KbolOSwdcZ+QKxUjetVc xa8WX6ygpiPsGvuShwnR4PbpHB7z/EeptAejv2GUqNJFcKErWR/zKfb8eP0Pm3qDaFz7fg4mS49nx 7+73ZAQjAf6tIsudraP/l4ht7iwueW9O1NWTa2CeZxXqpv27fK+50A7uOJlDc05vipvOVajEcGTVm Hi5oOZ+gZiBVqWu/kUdxOyk0jasqPLpf+3Y55f44zPLiCHX6GM4uyExjIINiLRnfZOkXH/o2g5V9v Pwj6mhdA==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.100.1 #2 (Red Hat Linux)) id 1xODbG-00000000RDp-0n9y; Tue, 03 Nov 2026 12:26:50 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id B3E11301185; Tue, 03 Nov 2026 13:26:47 +0100 (CET) Date: Tue, 3 Nov 2026 13:26:47 +0100 From: Peter Zijlstra To: kernel test robot Cc: oe-lkp@lists.linux.dev, lkp@intel.com, linux-kernel@vger.kernel.org, Andrew Morton , Finn Thain , Geert Uytterhoeven , Sasha Levin , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Ard Biesheuvel , "H. Peter Anvin" , Alexei Starovoitov , Andrii Nakryiko , Arnd Bergmann , Boqun Feng , Daniel Borkman , Dinh Nguyen , Eduard Zingerman , Gary Guo , Guo Ren , Hao Luo , Jiri Olsa , John Fastabend , John Paul Adrian Glaubitz , Jonas Bonn , KP Singh , Marc Rutland , Martin KaFai Lau , Rich Felker , Song Liu , Stafford Horne , Stanislav Fomichev , Stefan Kristiansson , Will Deacon , Yonghong Song , Yoshinori Sato , david@kernel.org, liam@infradead.org, kas@kernel.org Subject: Re: [linus:master] [atomic] 80047d84ee: WARNING:at_include/linux/instrumented.h:#__split_huge_pmd_locked Message-ID: <20261103122647.GL1813469@noisy.programming.kicks-ass.net> References: <202611022259.def3e086-lkp@intel.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <202611022259.def3e086-lkp@intel.com> On Tue, Nov 03, 2026 at 08:58:07AM +0800, kernel test robot wrote: > > > Hello, > > kernel test robot noticed "WARNING:at_include/linux/instrumented.h:#__split_huge_pmd_locked" on: > > commit: 80047d84eed25e9c92cfb9169980a0dfec110246 ("atomic: add alignment check to instrumented atomic operations") https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > [test failed on linux-next/master 7649ba73f9e7e1e04d0b46213e39c79ae09dd55c] > > in testcase: trinity > with following parameters: > > runtime: 300s > group: group-02 > nr_groups: 5 > > > config: i386-randconfig-1005-20261101 > compiler: gcc-14 > test machine: qemu-system-i386 -enable-kvm -cpu Icelake-Server-noTSX,enforce,lm=off -smp 4 -m 4G > > (please refer to attached dmesg/kmsg for entire log/backtrace) > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags > | Reported-by: kernel test robot > | Closes: https://lore.kernel.org/oe-lkp/202611022259.def3e086-lkp@intel.com > > > [ 18.704659][ T3738] ------------[ cut here ]------------ > [ 18.706815][ T3738] WARNING: include/linux/instrumented.h:62 at __split_huge_pmd_locked+0x6d2/0xac0, CPU#0: trinity-c1/3738 > [ 18.717796][ T3738] Modules linked in: > [ 18.719286][ T3738] CPU: 0 UID: 65534 PID: 3738 Comm: trinity-c1 Not tainted 6.19.0-rc6-00100-g80047d84eed2 #1 PREEMPT(lazy) > [ 18.723193][ T3738] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 > [ 18.726644][ T3738] EIP: __split_huge_pmd_locked (x86/include/asm/pgtable.h:228 (discriminator 1) huge_memory.c:3128 (discriminator 1)) > [ 18.728717][ T3738] Code: dc 85 d2 75 0c c6 45 c2 00 85 c0 0f 84 ee fe ff ff f6 45 bc 03 0f 85 47 03 00 00 8b 45 bc 80 08 10 c6 45 c2 01 e9 d5 fe ff ff <0f> 0b 0f c7 4d ec 0f 84 34 fd ff ff eb f2 e8 db 58 40 01 85 c0 0f > All code > ======== > 0: dc 85 d2 75 0c c6 faddl -0x39f38a2e(%rbp) > 6: 45 c2 00 85 rex.RB ret $0x8500 > a: c0 0f 84 rorb $0x84,(%rdi) > d: ee out %al,(%dx) > e: fe (bad) > f: ff (bad) > 10: ff f6 push %rsi > 12: 45 bc 03 0f 85 47 rex.RB mov $0x47850f03,%r12d > 18: 03 00 add (%rax),%eax > 1a: 00 8b 45 bc 80 08 add %cl,0x880bc45(%rbx) > 20: 10 c6 adc %al,%dh > 22: 45 c2 01 e9 rex.RB ret $0xe901 > 26: d5 fe ff ff {rex2 0xfe} ud0 %r23,%r31 > 2a:* 0f 0b ud2 <-- trapping instruction > 2c: 0f c7 4d ec cmpxchg8b -0x14(%rbp) > 30: 0f 84 34 fd ff ff je 0xfffffffffffffd6a > 36: eb f2 jmp 0x2a AFAICT this is pxx_xchg64() from the PAE code operating on an on-stack pmd value. The below 'fixes' it, but the question is of course, WTF are we using an on-stack pmd value for set_pmd(). --- diff --git a/arch/x86/include/asm/pgtable-3level_types.h b/arch/x86/include/asm/pgtable-3level_types.h index 580b09bf6a45..b1343a1dc55a 100644 --- a/arch/x86/include/asm/pgtable-3level_types.h +++ b/arch/x86/include/asm/pgtable-3level_types.h @@ -5,12 +5,12 @@ #ifndef __ASSEMBLER__ #include -typedef u64 pteval_t; -typedef u64 pmdval_t; -typedef u64 pudval_t; -typedef u64 p4dval_t; -typedef u64 pgdval_t; -typedef u64 pgprotval_t; +typedef u64 __aligned(8) pteval_t; +typedef u64 __aligned(8) pmdval_t; +typedef u64 __aligned(8) pudval_t; +typedef u64 __aligned(8) p4dval_t; +typedef u64 __aligned(8) pgdval_t; +typedef u64 __aligned(8) pgprotval_t; typedef union { struct {