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linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, fuse-devel@lists.linux.dev Subject: Re: [PATCH v4 07/38] mm: add mmap action for discontiguous kernel page mapping Message-ID: References: <20261003-b4-mmap-prepare-vma-flag-sanify-v4-0-a1f052500fd7@kernel.org> <20261003-b4-mmap-prepare-vma-flag-sanify-v4-7-a1f052500fd7@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 713C0180008 X-Stat-Signature: dp679z9d5f757xdyua5ymu3cz66ajows X-HE-Tag: 1791564993-145831 X-HE-Meta: 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GQ/VGYU++6a1g+r1NmJo2fqrNndSVeclnQWKjo/7PbS5ulzLzWSg5YISyX++HZeytX4fyu9UdHRdhvSmI+cHMSrq6oiQjFzLVIaqTh+/rVxKX+xSQvP/lfjtvbTUKBRdBxAOfzZ7vH4W5ZU8WYD2e6KqdgYMobcK7VCwiwL8T9ZrPStt9sMNH4yGnBO9GCqCl+Psl/GZNnQ/xnjpt1rFGjvjyNPMuuBy+XQYjSzESwIuVgs4bUSmI1YmMAHo2UB4GdX8CG5wRvUyTKa8uDpijfQ8FwSQ9k7zWjnXLVfkHAD4bMoeg1h4Kcj5h/8m765vU/tFHz7118Ufjs3mc4WtMEAu9Dm0nzd4sVhJaTVf/yIIrFUHQBUYxD Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sun, Oct 04, 2026 at 10:11:18AM -0700, Suren Baghdasaryan wrote: > On Sat, Oct 3, 2026 at 6:35 PM Lorenzo Stoakes (ARM) wrote: > > diff --git a/mm/memory.c b/mm/memory.c > > index 448342883e9d..45b21bb04a18 100644 > > --- a/mm/memory.c > > +++ b/mm/memory.c > > +static void __map_kernel_pages_prepare(struct vm_area_desc *desc) > > +{ > > + if (vma_desc_test(desc, VMA_MIXEDMAP_BIT)) > > + return; > > + > > + VM_WARN_ON_ONCE(mmap_read_trylock(desc->mm)); > > Sorry I missed this before and it is pre-existing code but is this a > weird way of asserting that mmap_lock is write-locked? If so, why not > just use mmap_assert_write_locked()? Ah yeah, this weirdness is duplicated from the existing code. Will fix up on resin! -- Cheers, Lorenzo