From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793721506; b=kgVyDV3DSu4VBMpU2wM2hicjvOOr4d+hBEYwAhctva3LmmJuoALbmW5SxlIrtZNEH7Nk qnI1JLLXTIzgVX1+3Jf0Ri48w5jY/J8aeMAm0fW9rRmCGT36BIFsvBPeABZcrQXVCJshu jKjLM2dECaRrS7gW4ZcpUaUaK1ox3gwgCevq3IMkoTYGVccT/CHH1dq/2TshkjvD9zrR9 368KAQ82D0sBMxATvwYgRuOsg9rv+vHcYitFW5cQrsHxFDjet65pdfr6jt7pzqj8cxP/k fAuwK54XifrjBR0sVWThE3mIdcHNmLAHHpLVrGrYwggRSI1mCb3Fc7kBP+WY3ANEjzg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793721506; h=Received:DKIM-Signature:Message-ID:Date:MIME-Version:User-Agent: Subject:To:Cc:References:From:Content-Language:Autocrypt:In-Reply-To: Content-Type:Content-Transfer-Encoding; bh=JqAbBArnfd9sGvHzBu7RCGdZFbliWnjLETcd43LEOk0=; b=H7dUeweaaCKmVG9zKBOFo0tUK/u9QcBDFGhsVCTJuWa3AsNp+SRFyEZ8cH8gMxPplbkM UXNjhVVkQCgDXU/lRavopByNnpNHqAr2NsyzCAnu/+6J8ZAxMOUW/Dy8NtXWrFxIy4TsA K+GtynadaXVJhQnKhb0cAG2MWIT1Z4EDpssTQnxX9Y4lOs0gghoeTvUr9B4AvEIzj8S10 fyUA7EeZB9Rh8jrZ7spkHkEREc6I9FZ67gY1Wz67oSBXTx0danFerqh7p3HGxDKSIoqTq YHtnyRAp5xxOn1rUDGNWonux77ahOQCtN10HrkHvX1C+0Puha5k50VyQKN1L00YtaJQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="DM/7hmIN"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5C20A6082BC0; Tue, 3 Nov 2026 15:58:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=DM/7hmIN Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1516F1F000C1; Tue, 3 Nov 2026 15:58:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793721505; bh=JqAbBArnfd9sGvHzBu7RCGdZFbliWnjLETcd43LEOk0=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=DM/7hmINCL+8X0W3ZvLL0XvE9tV8CvUnxlEsjtRGHUGbpVMpfbkJUYvIPDQppZ7R5 VTnveTCAQOO60eLu7ghdrvvXi2sglUoQQgtiLVvNOUJErdmv+YrUSWo1qtINUKO1zn Dk4+3GrccAEKF7NVSV8zEfWvEvMn1y5fMvUSegc2EymARq3X/wRsXDHp70FoaHXSD9 wr2VgziPHejBsSgp/RCXnHqyvEdOJ6iDV59uU6sSqIa+Y4tfVXjbhMNS8cxrCMmRlV poYLZgAhU4H+rf5J5/RnxL/MZkzOovIzGsHkjtV9u7q5wI9Re5Z1scO1Rh/LTEe3hN vBLMh3IFx/kmA== Message-ID: <1dbf6b30-15c7-4371-9711-c658a0fc1b50@kernel.org> Date: Tue, 3 Nov 2026 16:58:09 +0100 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 User-Agent: Mozilla Thunderbird Subject: Re: [linus:master] [atomic] 80047d84ee: WARNING:at_include/linux/instrumented.h:#__split_huge_pmd_locked To: Andrew Morton , Peter Zijlstra Cc: kernel test robot , oe-lkp@lists.linux.dev, lkp@intel.com, linux-kernel@vger.kernel.org, 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 , liam@infradead.org, kas@kernel.org, Dave Hansen , Muhammad Usama Anjum References: <202611022259.def3e086-lkp@intel.com> <20261103122647.GL1813469@noisy.programming.kicks-ass.net> <20261103074305.27bfc570fb81346860867bdc@linux-foundation.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20261103074305.27bfc570fb81346860867bdc@linux-foundation.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/3/26 16:43, Andrew Morton wrote: > On Tue, 3 Nov 2026 13:26:47 +0100 Peter Zijlstra wrote: > >> 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(). >> >> --- 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; >> > > (cc Dave) > > fwiw this was discussed a couple of years ago but nothing really came > of it. > > https://lore.kernel.org/20240401185451.6897208962d3fc47a12ffb5a@otheo.eu IIUC Usama has some things in the works that will avoid on-stack pmds. -- Cheers, David