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 0EE0C265CAD for ; Tue, 30 Jun 2026 23:06:57 +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=1782860819; cv=none; b=ULyLBpBhydqiZIryofZeGHEVxqwg+RBmbQP1944CFIwCz37RRXDQtEQQHEgD4e5lY1s27L45YISIvpNQzgZqeLAIUdyz/4p4JyU01cOIYYJN5uNNfC+abjNuwcVhtYyqShb3h+g8/bugfJ0GlKdGqdcnd6tg6Gk2Oe3iN5q2iUY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782860819; c=relaxed/simple; bh=gOh9Fg6zpNIWp95rkKvJc3p8TAb3bscTAQ2UtwMdD+I=; h=Date:To:From:Subject:Message-Id; b=hW4e0NpIFIH1upLJEXOUwpvvATK4f+F3i2MaKkpwmyq3NgBSym7oIS1iphcD6heyvlXEnlM1tiPk+PBcCx7egyuhDLPwyWOJ5LRpdG2cIiu0arGXkr+0mfqwVjPhzIaZntDg6mdK6nfg3itJjYtGt/8/kfmeqPEhT7HfnqBBrdo= 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=EWHyJrEO; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="EWHyJrEO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9ABB91F000E9; Tue, 30 Jun 2026 23:06:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1782860817; bh=mxmtvQ6+0CNAaBe401yTDL7FrboywnDgW6M2dL5L60A=; h=Date:To:From:Subject; b=EWHyJrEOz/swP7TSXAKPLRNQvO9Mmz2dt0/2PN5LUzdA9RzH2BbiSlx9fe8rup8Jf cAamandTsnXS4VClPVBIAdX5wVITHXsUg6UAPpXRHIbCDclvu69iqpgsjfYgCaRhh+ pmufVEUfrljf8M1Hcm70fjezAZiueGr2C46ckjUM= Date: Tue, 30 Jun 2026 16:06:57 -0700 To: mm-commits@vger.kernel.org,will@kernel.org,riel@surriel.com,peterz@infradead.org,mingo@redhat.com,longman@redhat.com,joe@perches.com,jgg@ziepe.ca,clm@meta.com,cel@kernel.org,boqun.feng@gmail.com,liam@infradead.org,akpm@linux-foundation.org From: Andrew Morton Subject: + maple_tree-drop-dead-code-from-mas_extend_spanning_null.patch added to mm-new branch Message-Id: <20260630230657.9ABB91F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: maple_tree: drop dead code from mas_extend_spanning_null() has been added to the -mm mm-new branch. Its filename is maple_tree-drop-dead-code-from-mas_extend_spanning_null.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-drop-dead-code-from-mas_extend_spanning_null.patch This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new. The mm-new branch of mm.git is not included in linux-next If a few days of testing in mm-new is successful, the patch will me moved into mm.git's mm-unstable branch, which is included in linux-next 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 various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: "Liam R. Howlett (Oracle)" Subject: maple_tree: drop dead code from mas_extend_spanning_null() Date: Tue, 30 Jun 2026 15:08:29 -0400 mas_extend_spanning_null() had a clause if the end of the range being written (mas->last) is the same as the end of the existing range it is overwriting (wr_mas->r_max), action will be taken. This code path is not possible because the only calling function increments mas->last (unless it's ULONG_MAX) to walk to one beyond the write and then resets the value back to the initial value. In the case of mas->last == ULONG_MAX, then the second part of the statement will always be false - mas->last cannot be less than the node max. This code never executed and is flawed anyways (the arguments are incorrectly ordered), so removing it is the safest action. Since the code never executes, it is not fixing any issue so Fixes tag is not given. Link: https://lore.kernel.org/20260630190843.3563858-6-liam@infradead.org Signed-off-by: Liam R. Howlett (Oracle) Cc: Boqun Feng Cc: Chris Mason Cc: Chuck Lever Cc: Ingo Molnar Cc: Jason Gunthorpe Cc: Joe Perches Cc: Peter Zijlstra Cc: Rik van Riel Cc: Waiman Long Cc: Will Deacon Signed-off-by: Andrew Morton --- lib/maple_tree.c | 7 ------- 1 file changed, 7 deletions(-) --- a/lib/maple_tree.c~maple_tree-drop-dead-code-from-mas_extend_spanning_null +++ a/lib/maple_tree.c @@ -2996,13 +2996,6 @@ static inline void mas_extend_spanning_n if (r_mas->last < r_wr_mas->r_max) r_mas->last = r_wr_mas->r_max; r_mas->offset++; - } else if ((r_mas->last == r_wr_mas->r_max) && - (r_mas->last < r_mas->max) && - !mas_slot_locked(r_mas, r_wr_mas->slots, r_mas->offset + 1)) { - r_mas->last = mas_safe_pivot(r_mas, r_wr_mas->pivots, - r_wr_mas->type, r_mas->offset + 1); - r_mas->offset++; - r_wr_mas->r_max = r_mas->last; } } _ Patches currently in -mm which might be from liam@infradead.org are maple_tree-add-rcu-locking-check-when-lockdep-is-enabled.patch locking-lockdep-add-sequence-counter-to-held_lock.patch maple_tree-add-write-lock-checking-with-lockdep-sequence-numbers.patch maple_tree-documentation-fix.patch maple_tree-drop-dead-code-from-mas_extend_spanning_null.patch maple_tree-drop-maple_alloc_slots.patch maple_tree-clarify-comments-on-mas_nomem.patch maple_tree-use-prefetched-value-in-mas_wr_store_type.patch maple_tree-optimise-mas_wr_node_store-when-not-in-rcu-mode.patch maple_tree-micro-optimisation-of-mas_wr_store_type.patch maple_tree-add-bulk-parent-set-helper.patch maple_tree-catch-race-in-mas_alloc_cyclic.patch maple_tree-document-that-erase-may-use-gfp_kernel-for-allocations.patch maple_tree-warn_on_once-when-allocations-fail.patch maple_tree-document-erase-and-allocations-better.patch maple_tree-change-two-gfp-flags-in-tests.patch maple_tree-fix-argument-name-in-header.patch maple_tree-avoid-extra-gap-calculation.patch maple_tree-add-helper-mas_make_walkable.patch