From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E58C527A476 for ; Wed, 4 Feb 2026 17:06:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770224780; cv=none; b=bpPpd/6ofrrUxC0YuX1qUM1Z63XrKKL/NlaZTq4AH2JqkG1ubSamavnMnh/1Pc5ccGnnvsRsNZzdwYxJOfoxMYJBdRBODrsMW5X+MpiTb/Ifhm/bGc+Gg4jdi+VP+HasZwPhJ4qe/oMSUncjoeIhrDYA2CqyG/M5Y/9UzP75A3Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770224780; c=relaxed/simple; bh=Gg+sAcLZwfm3uqlhJcCOOiCag92u0eUCaiU5G7zLXzQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=IJXtG54uWOu7fCbU9BbC5zD9nG1UGNyg4VfABCqmJU34V02x9Gj9rGBIWEdhcse/iC4xwMlBEXg3ZfOBfNsGuQBxqVFmc3vTlll4pSpM2aR6pVAVfqzJqfjg9kUAhEf7T5PUNoBZyBXPHc6PI4E+y/1nz0xPtKEFSBqwdINNCNI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zHROY0cR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zHROY0cR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E0DE8C4CEF7; Wed, 4 Feb 2026 17:06:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1770224779; bh=Gg+sAcLZwfm3uqlhJcCOOiCag92u0eUCaiU5G7zLXzQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=zHROY0cR7w3lcBJgGsyf/Cv45Tfg6FMqs28GW6CkeVc+K4ToLsz+pN4buO0W7I47s Ib3DomSvw+gyDBRprhnK2FqxCG75cbWKQGsxGPb1ykGTkqTetr60SqIbi3MIKjmpoC xfEoFunaXofMnaHU2e1VBffIriv3cm9RXmuKn2e0= Date: Wed, 4 Feb 2026 18:06:16 +0100 From: Greg KH To: Suren Baghdasaryan Cc: Sasha Levin , stable@vger.kernel.org, Ran Xiaokai , Pratyush Yadav , Pasha Tatashin , "Mike Rapoport (Microsoft)" , Alexander Graf , Kent Overstreet , Andrew Morton Subject: Re: [PATCH 6.18.y] kho: init alloc tags when restoring pages from reserved memory Message-ID: <2026020427-germinate-pastor-aa8f@gregkh> References: <2026020303-drippy-appliance-a74c@gregkh> <20260204002654.1462558-1-sashal@kernel.org> <2026020419-extortion-swinging-6394@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Wed, Feb 04, 2026 at 08:46:35AM -0800, Suren Baghdasaryan wrote: > On Wed, Feb 4, 2026 at 1:59 AM Greg KH wrote: > > > > On Tue, Feb 03, 2026 at 07:26:54PM -0500, Sasha Levin wrote: > > > From: Ran Xiaokai > > > > > > [ Upstream commit e86436ad0ad2a9aaf88802d69b68f02cbd1f04a9 ] > > > > > > Memblock pages (including reserved memory) should have their allocation > > > tags initialized to CODETAG_EMPTY via clear_page_tag_ref() before being > > > released to the page allocator. When kho restores pages through > > > kho_restore_page(), missing this call causes mismatched > > > allocation/deallocation tracking and below warning message: > > > > > > alloc_tag was not set > > > WARNING: include/linux/alloc_tag.h:164 at ___free_pages+0xb8/0x260, CPU#1: swapper/0/1 > > > RIP: 0010:___free_pages+0xb8/0x260 > > > kho_restore_vmalloc+0x187/0x2e0 > > > kho_test_init+0x3c4/0xa30 > > > do_one_initcall+0x62/0x2b0 > > > kernel_init_freeable+0x25b/0x480 > > > kernel_init+0x1a/0x1c0 > > > ret_from_fork+0x2d1/0x360 > > > > > > Add missing clear_page_tag_ref() annotation in kho_restore_page() to > > > fix this. > > > > > > Link: https://lkml.kernel.org/r/20260122132740.176468-1-ranxiaokai627@163.com > > > Fixes: fc33e4b44b27 ("kexec: enable KHO support for memory preservation") > > > Signed-off-by: Ran Xiaokai > > > Reviewed-by: Pratyush Yadav > > > Reviewed-by: Pasha Tatashin > > > Reviewed-by: Mike Rapoport (Microsoft) > > > Cc: Alexander Graf > > > Cc: Kent Overstreet > > > Cc: Suren Baghdasaryan > > > Cc: > > > Signed-off-by: Andrew Morton > > > Signed-off-by: Sasha Levin > > > --- > > > kernel/kexec_handover.c | 8 ++++++++ > > > 1 file changed, 8 insertions(+) > > > > > > diff --git a/kernel/kexec_handover.c b/kernel/kexec_handover.c > > > index 03d12e27189fc..db08c1a2e1f80 100644 > > > --- a/kernel/kexec_handover.c > > > +++ b/kernel/kexec_handover.c > > > @@ -260,6 +260,14 @@ static struct page *kho_restore_page(phys_addr_t phys) > > > if (info.order > 0) > > > prep_compound_page(page, info.order); > > > > > > + /* Always mark headpage's codetag as empty to avoid accounting mismatch */ > > > + clear_page_tag_ref(page); > > > + if (!is_folio) { > > > + /* Also do that for the non-compound tail pages */ > > > + for (unsigned int i = 1; i < nr_pages; i++) > > > + clear_page_tag_ref(page + i); > > > + } > > > + > > > > Breaks the build :( > > Which config? I built both defconfig and CONFIG_MEM_ALLOC_PROFILING=y, > they didn't fail. Could you please send me your failing config? is_folio is not defined in this function, how are you even building this file? thanks, greg k-h