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Date:   Fri, 26 Jun 2020 01:36:26 -0700 (PDT)
From:   "Kenneth R. Crudup" <kenny@panix.com>
Reply-To: "Kenneth R. Crudup" <kenny@panix.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>
cc:     Christoph Hellwig <hch@lst.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Commit 25f12ae45fc1 ("maccess: rename probe_kernel_address to
 get_kernel_nofault") causing several OOPSes
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On Sun, 21 Jun 2020, Linus Torvalds wrote:

> For me that patch makes no difference.

So ... it looks like this original issue (random crashes if this commit was
made and the ROMs thing isn't patched) is a red herring.

For some time now, my Thunderbolt adapter (Lenovo 2nd-Gen TB dock) sometimes
... "acts up" on reboots/powerons with my laptop (Dell XPS 13 2-in-1) if I
boot with it connected- I'll get random disconnects and/or lack of external
video and/or its internal devices will drop offline. I suspect these crashes
were related to the PCIe scribbling(?) somewhere(?) (even though I have IOMMU
turned on). I can't track it down, and I think the issue may lie somewhere
either with the Thunderbolt subsystem (my TB domain UUID gets regenerated on
every boot and is always changing) or a bug in this Dell's BIOS (probably
the likely culprit).

... in any case, I booted a fresh branch that does contain the commit in the
 Subject: line, and w/o Christoph's ROMs patch and as long as I don't boot
with the TB adapter attached (or from a cold boot- SOMEtimes) it seems to
work. So, my apologies for wasting everyone's time.

	-Kenny

-- 
Kenneth R. Crudup  Sr. SW Engineer, Scott County Consulting, Orange County CA