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Peter Anvin" , Mike Rapoport , Lorenzo Stoakes , Toshi Kani , linux-mm@kvack.org, regressions@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] x86/mm: Drop the page allocation from pud_free_pmd_page() Date: Fri, 25 Sep 2026 01:39:15 +0500 Message-ID: <20260924203915.189167-1-mikhail.v.gavrilov@gmail.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On 9/24/26 10:21, Dave Hansen wrote: > OK, I've got a version of Mikhail's fix with a changelog and comments > I've munged a bit: > >> https://git.kernel.org/pub/scm/linux/kernel/git/daveh/devel.git/log/?h=pmdfree > > Does that look OK to everyone? Looks good to me, thanks. The code is v2 with your comments and the declarations reordered, so the testing done for v2 still applies. Two small things, both optional: - "The new mmap_read_lock() is held over a GFP_KERNEL allocation": the lock held over the allocation is the same init_mm lock, but taken in vmap_try_huge_pud(), not the new one in CPA. Maybe "The huge vmap code holds the same lock over a GFP_KERNEL allocation, which is a no-no now that reclaim can take it." - The kernel-doc lost its "Return:" line while the function still returns int, so kernel-doc -Wreturn will complain about it.