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 EE765219EB for ; Tue, 7 Jan 2025 03:07:15 +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=1736219236; cv=none; b=a1FHutgqzpJ/aJzh0TGjSik3opzwD0+e1OAScneXC4dWQlREgeJ/hj0OWuZBzVN5erpsaNxOohJ2bCKzTwFy5zZq074pi3IG0nHH6OXy7RroWMKNhyAVpOOwzGHH6zmcCVwSOOJv+DqNqUeYeEzfeVjpsWT32VwrucOpefNymPU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736219236; c=relaxed/simple; bh=ljrhpV4TAhnxD0/N53jacIptJXQQDmlQpSFjPpeBwkc=; h=Date:To:From:Subject:Message-Id; b=ERUwIvC4rEot/SS5bmVkg7L9FzsySIKMBMIZ7zawARvYUoMC6GeKubjiOnkRQEIC/H7R+WVEOdK150njG4paUvOKtkwAzuY/CEB6MNNbG+yqdEnQVrpvcb/Vam6K1R3w0YY4P+Xzm3xPZZjaHVcV4ui+D0miDbgb2wN5bG03FwY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=pu1O06M7; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="pu1O06M7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 75CEFC4CED2; Tue, 7 Jan 2025 03:07:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1736219235; bh=ljrhpV4TAhnxD0/N53jacIptJXQQDmlQpSFjPpeBwkc=; h=Date:To:From:Subject:From; b=pu1O06M7PKAYHPoFh/dx/N8RTY0sw3RlcFCzJ4SNTTIUO18nZk3xlOBKI/6J3+Ol1 RbT+znPu5KP2JNWfXnNwY+FztMSX99qFyZbfReKIhuj4zR3HrZeMLJd3blLjNIbPme KJAfu2yFwdpfiMuLm8twC4JNFevXPSQ1vLFUPUJY= Date: Mon, 06 Jan 2025 19:07:14 -0800 To: mm-commits@vger.kernel.org,rppt@kernel.org,catalin.marinas@arm.com,guoweikang.kernel@gmail.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-memmap-prevent-double-scanning-of-memmap-by-kmemleak.patch added to mm-unstable branch Message-Id: <20250107030715.75CEFC4CED2@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm/memmap: prevent double scanning of memmap by kmemleak has been added to the -mm mm-unstable branch. Its filename is mm-memmap-prevent-double-scanning-of-memmap-by-kmemleak.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memmap-prevent-double-scanning-of-memmap-by-kmemleak.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Guo Weikang Subject: mm/memmap: prevent double scanning of memmap by kmemleak Date: Mon, 6 Jan 2025 10:11:25 +0800 kmemleak explicitly scans the mem_map through the valid struct page objects. However, memmap_alloc() was also adding this memory to the gray object list, causing it to be scanned twice. Remove memmap_alloc() from the scan list and add a comment to clarify the behavior. Link: https://lore.kernel.org/lkml/CAOm6qn=FVeTpH54wGDFMHuCOeYtvoTx30ktnv9-w3Nh8RMofEA@mail.gmail.com/ Link: https://lkml.kernel.org/r/20250106021126.1678334-1-guoweikang.kernel@gmail.com Signed-off-by: Guo Weikang Reviewed-by: Catalin Marinas Cc: Mike Rapoport (Microsoft) Signed-off-by: Andrew Morton --- include/linux/memblock.h | 4 ++++ mm/mm_init.c | 8 ++++++-- mm/sparse-vmemmap.c | 5 +++-- 3 files changed, 13 insertions(+), 4 deletions(-) --- a/include/linux/memblock.h~mm-memmap-prevent-double-scanning-of-memmap-by-kmemleak +++ a/include/linux/memblock.h @@ -378,6 +378,10 @@ static inline int memblock_get_region_no /* Flags for memblock allocation APIs */ #define MEMBLOCK_ALLOC_ANYWHERE (~(phys_addr_t)0) #define MEMBLOCK_ALLOC_ACCESSIBLE 0 +/* + * MEMBLOCK_ALLOC_NOLEAKTRACE avoids kmemleak tracing. It implies + * MEMBLOCK_ALLOC_ACCESSIBLE + */ #define MEMBLOCK_ALLOC_NOLEAKTRACE 1 /* We are using top down, so it is safe to use 0 here */ --- a/mm/mm_init.c~mm-memmap-prevent-double-scanning-of-memmap-by-kmemleak +++ a/mm/mm_init.c @@ -1585,13 +1585,17 @@ void __init *memmap_alloc(phys_addr_t si { void *ptr; + /* + * Kmemleak will explicitly scan mem_map by traversing all valid + * `struct *page`,so memblock does not need to be added to the scan list. + */ if (exact_nid) ptr = memblock_alloc_exact_nid_raw(size, align, min_addr, - MEMBLOCK_ALLOC_ACCESSIBLE, + MEMBLOCK_ALLOC_NOLEAKTRACE, nid); else ptr = memblock_alloc_try_nid_raw(size, align, min_addr, - MEMBLOCK_ALLOC_ACCESSIBLE, + MEMBLOCK_ALLOC_NOLEAKTRACE, nid); if (ptr && size > 0) --- a/mm/sparse-vmemmap.c~mm-memmap-prevent-double-scanning-of-memmap-by-kmemleak +++ a/mm/sparse-vmemmap.c @@ -31,6 +31,8 @@ #include #include +#include "internal.h" + /* * Allocate a block of memory to be used to back the virtual memory map * or to back the page tables that are used to create the mapping. @@ -42,8 +44,7 @@ static void * __ref __earlyonly_bootmem_ unsigned long align, unsigned long goal) { - return memblock_alloc_try_nid_raw(size, align, goal, - MEMBLOCK_ALLOC_ACCESSIBLE, node); + return memmap_alloc(size, align, goal, node, false); } void * __meminit vmemmap_alloc_block(unsigned long size, int node) _ Patches currently in -mm which might be from guoweikang.kernel@gmail.com are mm-kmemleak-fix-percpu-memory-leak-detection-failure.patch mm-shmem-refactor-to-reuse-vfs_parse_monolithic_sep-for-option-parsing.patch mm-early_ioremap-add-null-pointer-checks-to-prevent-null-pointer-dereference.patch mm-memblock-add-memblock_alloc_or_panic-interface.patch mm-memmap-prevent-double-scanning-of-memmap-by-kmemleak.patch