From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 BC3FA38C41B; Tue, 30 Jun 2026 10:54:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782816864; cv=none; b=pgAtvysTs4OpBZiwfDv4xAptjcumgkj9ZzIhWWOJ+w5OGHDmZTPGdYk9xmViO9CtkxbTQp7qI8gz+KQ+paJpbjcXqX4WcDG5iun23e9cyGCE9/Ls2/xMMjTEVMVavo6oLblxVrLkDi8RmCBWDVlroOQnSHQKjE3iLnNS2lqeeps= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782816864; c=relaxed/simple; bh=h/gEhfrUJha1kZVU8awchaudZMXL+KTCgzMarIdQPmc=; h=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To:Cc; b=HIWfOElikMgJ8xw56Ye22ojIwzKpL7FwoyPZEk/PN2PRQkxz9J3z1ro/wEl1SaMFLUAhfhqNzHNgQLdMLvmnIUNbmwajdn+sh2md07/TNu9lXok9oUBIF21TDcrIv0qEuGNd51g4Y24aaTMcP7cLGI8SZ3UX4hXrfnwaFfv+jQM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fJgceCav; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fJgceCav" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2563F1F000E9; Tue, 30 Jun 2026 10:54:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782816863; bh=FnV8WNv2U/2NeCf/652mdSlf9RYHKUxm9hACRNRtpLQ=; h=From:Subject:Date:To:Cc; b=fJgceCavbNPcF66SdZ9l13sifefI0sGJa2R/z+GKzBrF6OvGDYZL9bxpDhALEYZfg B+OQ9FyUviVgK11A9a03ctqjcK1DF0Zkcw8ZPHNR++4Gn83wGnDEYjJVjgMwN0K0jm krV3K2OueN3a6Hvez+zmYWyAPzsRP9jxD+m9prbSRIIbyghVlpOmvsJ6uq+JpWTa8T KdvIxZ1KHQRxye+1mO5tSoXGtsqWbl7ZVCJVHsbyyCPLsSUY3eCYmeNEUH60ZADbNU VhftXGA08ItqiRlKnf37DEIAlMF+a4DKeh5D+AFXfXhJO6Cp79/Y0qO4UarPwEcDJq ZffD7riVNrXkQ== From: "Mike Rapoport (Microsoft)" Subject: [PATCH 0/4] scsi: replace __get_free_pages() with kmalloc() Date: Tue, 30 Jun 2026 13:54:17 +0300 Message-Id: <20260630-b4-scsi-v1-0-494fb37ebe7b@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-B4-Tracking: v=1; b=H4sIAFmgQ2oC/yWM0QrCMAxFf2Xk2WA76lB/RXxo2sxFsEqiMhj79 7X6eC7n3AWMVdjg3C2g/BWTZ6ngdx2kKZYbo+TK0Lt+cIP3SAEtmWB25JjC8XQYA1T7pTzK/Hu 6XP9sH7pzere8GRSNkTSWNLWJwl7zI8K6bqAOpNyFAAAA X-Change-ID: 20260611-b4-scsi-d0b0eb4895f4 To: "Martin K. Petersen" Cc: Brian King , "James E.J. Bottomley" , Matthew Wilcox , Mike Rapoport , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org X-Mailer: b4 0.15.2 This is a (small) part of larger work of replacing page allocator calls with kmalloc. My initial intention a few month ago was to remove ugly casts [1], but then willy pointed out that Linus objected to something like this [2] and it looks like more than a decade old technical debt. Largely, anything that doesn't need struct page (or a memdesc in the future) should just use kmalloc() or kvmalloc() to allocate memory. kmalloc() guarantees alignment, physical contiguity and working virt_to_phys() and beside nicer API that returns void * on alloc and doesn't require to know the allocation size on free, kmalloc() provides better debugging capabilities than page allocator. Another thing is that touching these allocation sites gives the reviewers opportunity to see if a PAGE_SIZE buffer is actually needed or maybe another size is appropriate. For larger allocations that don't need physically contiguous memory kvmalloc() can be a better option that __get_free_pages() because under memory pressure it's is easier to allocate several order-0 pages than a physically contiguous chunk with the same number of pages. And last, but not least, removing needless calls to page allocator should help with memdesc (aka project folio) conversion. There will be way less places to audit to see if the user was actually using struct page. Also in git: https://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux.git gfp-to-kmalloc/scsi [1] https://lore.kernel.org/all/20251018093002.3660549-1-rppt@kernel.org/ [2] https://lore.kernel.org/all/CA+55aFwp4iy4rtX2gE2WjBGFL=NxMVnoFeHqYa2j1dYOMMGqxg@mail.gmail.com/ --- Mike Rapoport (Microsoft) (4): scsi: target: file: use kmalloc() to allocate temporary protection buffer scsi: proc: use kmalloc() in proc writers scsi: ipr: use kmalloc() to allocate IPR dump buffer memory scsi: sym53c8xx_2: replace __get_free_pages() with kmalloc() drivers/scsi/ipr.c | 4 ++-- drivers/scsi/scsi_devinfo.c | 4 ++-- drivers/scsi/scsi_proc.c | 9 +++++---- drivers/scsi/sym53c8xx_2/sym_hipd.h | 4 ++-- drivers/target/target_core_file.c | 4 ++-- 5 files changed, 13 insertions(+), 12 deletions(-) --- base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482 change-id: 20260611-b4-scsi-d0b0eb4895f4 Best regards, -- Sincerely yours, Mike.