usb/84336: [usb] [reboot] instant system reboot when unmounting a powered off/unplugged+replugged USB device

M. Warner Losh imp at
Sun Jan 27 10:49:48 PST 2008

In message: <1201458988.2277.285.camel at Particle>
            Henrik Gulbrandsen <henrik at> writes:
: On Sat, 2008-01-26 at 20:40 -0700, M. Warner Losh wrote:
: > One of the things that I've been working on with someone (whose name
: > escapes me) and Bruce Evans is trying to address these issues.  One
: > problem we have today is that when the device return ENXIO, the buffer
: > cache retries the operation rather than failing it upstream.  There
: > are a number of issues with doing this, including fixing all the
: > filesystems to cope with errors.  I've committed a number of 'keep the
: > system from panicing' type fixes, but much works remains to be done.
: I'd like to think that I'm "someone" :-)

Yes.  Now that I see your name that's right.  I couldn't find it in my
email because I'm getting too old...

: While I agree with you that there is still work to do, I think most of
: it would actually be side issues not directly related to usb/46176 or
: usb/84336. Things should be working for USB memory sticks and cameras,
: but perhaps flash cards still trigger it, or file systems other than
: msdosfs have problems, or the fix happens to introduce a memory leak.
: All of these problems would be better handled with more specific PRs.
: Writing as the guy who actually spent two and a half hours in a futile
: attempt to reproduce this problem with all patches applied, I'd say that
: the usb/46176 problem has passed on. It is no more. It has ceased to be.
: This is an ex-bug! At least until someone tells me why I'm a fool! :-)

Yes.  I've found things much more stable.  With the currently
committed subset of the patches applied, there's still a few crashes
for me from time to time...


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