Re: vm_area at addr ffffffffc0800000 is not marked as VM_IOREMAP

From: Christoph Hellwig <hch@infradead.org>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
	Christoph Hellwig <hch@infradead.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	linux-mm <linux-mm@kvack.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	Daniel Borkmann <daniel@iogearbox.net>, bpf <bpf@vger.kernel.org>,
	Bjorn Helgaas <bhelgaas@google.com>,
	linux-pci@vger.kernel.org
Subject: Re: vm_area at addr ffffffffc0800000 is not marked as VM_IOREMAP
Date: Fri, 8 Mar 2024 07:04:13 -0800	[thread overview]
Message-ID: <Zeso7eNj1sBhH5zY@infradead.org> (raw)
In-Reply-To: <CAADnVQLP=dxBb+RiMGXoaCEuRrbK387J6B+pfzWKF_F=aRgCPQ@mail.gmail.com>

On Thu, Mar 07, 2024 at 07:49:16PM -0800, Alexei Starovoitov wrote:
> Ok. I think I figured it out.
> Please try the attached patch.

I don't think this is the right thing.  The probem is that
the PCI code shouldn't really be using ioremap_page_range if it is
not an ioremap area, but instead directly call into
vmap_range_noflush (or an added back vmap_range to avoid all the
duplication) similar to the vunmap case in vunmap_range.