On Fri, Dec 02, 2011 at 04:24:37PM -0500, John Baldwin wrote: > On 12/2/11 4:19 PM, Marius Strobl wrote: > >Author: marius > >Date: Fri Dec 2 21:19:14 2011 > >New Revision: 228209 > >URL: http://svn.freebsd.org/changeset/base/228209 > > > >Log: > > - In device_probe_child(9) check the return value of > > device_set_driver(9) > > when actually setting a driver as especially ENOMEM is fatal in these > > cases. > > - Annotate other calls to device_set_devclass(9) and > > device_set_driver(9) > > without the return value being checked and that are okay to fail. > > > > Reviewed by: yongari (slightly earlier version) > > Hmm, I've always thought that new-bus overused M_NOWAIT. There are a > few places where M_NOWAIT might be appropriate (e.g. from pccbb's > interrupt routine when a cardbus card is inserted), but the boot time > probe can certainly use M_WAITOK instead. Even the pccbb case could use > M_WAITOK if it were simply deferred to a taskqueue (which it probably > should be anyway, probing and attaching a driver to a new card is far > too expensive to do directly from an interrupt handler). >
In general the use of M_NOWAIT vs. M_WAITOK in bus methods is also very inconsistent across device drivers. We should decide how to handle the standard case, document it and fix things up accordingly ... I agree that M_WAITOK should be used in most of these cases. Marius _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
