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Date:   Sun, 23 Apr 2023 00:30:05 +0200
From:   Lukas Wunner <lukas@wunner.de>
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     linux-cxl@vger.kernel.org, ira.weiny@intel.com
Subject: Re: [PATCH] cxl/port: Fix port to pci device assumptions in
 read_cdat_data()
Message-ID: <20230422223005.GA12308@wunner.de>
References: <becaf70e8faf9681d474200117d62d7eaac46cca.1678543498.git.lukas@wunner.de>
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On Sat, Apr 22, 2023 at 01:54:00PM -0700, Dan Williams wrote:
> Lukas Wunner wrote:
> > On Sat, Apr 22, 2023 at 10:35:02AM +0200, Lukas Wunner wrote:
> > > I note however that before af0a6c3587dc, xa_for_each() was run on an
> > > xarray which was not initialized with xa_init() on non-pci cxl ports.
> > > (xa_init() was run from cxl_pci_probe() -> devm_cxl_pci_create_doe()
> > > but xa_for_each() was run from read_cdat_data() -> find_cdat_doe()
> > > for non-pci cxl ports as well.)
> > > 
> > > Hence can't this crash prior to af0a6c3587dc as well?
> > 
> > After taking another look with a fresh pair of eyeballs I think
> > you may see splats with CONFIG_DEBUG_LOCK_ALLOC=y (even prior to
> > af0a6c3587dc on non-pci cxl devices) due to the missing xa_init().
> 
> The xa_init() was included before in the removed call to
> devm_cxl_pci_create_doe().

... which was called from cxl_pci_probe(), so only if a pci_dev exists?

I guess I must be missing something...

Thanks,

Lukas