John Baldwin 06ad42b2f7 Close some races between procfs/ptrace and exit(2): ... - Reorder the events in exit(2) slightly so that we trigger the S_EXIT stop event earlier. After we have signalled that, we set P_WEXIT and then wait for any processes with a hold on the vmspace via PHOLD to release it. PHOLD now KASSERT()'s that P_WEXIT is clear when it is invoked, and PRELE now does a wakeup if P_WEXIT is set and p_lock drops to zero. - Change proc_rwmem() to require that the processing read from has its vmspace held via PHOLD by the caller and get rid of all the junk to screw around with the vmspace reference count as we no longer need it. - In ptrace() and pseudofs(), treat a process with P_WEXIT set as if it doesn't exist. - Only do one PHOLD in kern_ptrace() now, and do it earlier so it covers FIX_SSTEP() (since on alpha at least this can end up calling proc_rwmem() to clear an earlier single-step simualted via a breakpoint). We only do one to avoid races. Also, by making the EINVAL error for unknown requests be part of the default: case in the switch, the various switch cases can now just break out to return which removes a _lot_ of duplicated PRELE and proc unlocks, etc. Also, it fixes at least one bug where a LWP ptrace command could return EINVAL with the proc lock still held. - Changed the locking for ptrace_single_step(), ptrace_set_pc(), and ptrace_clear_single_step() to always be called with the proc lock held (it was a mixed bag previously). Alpha and arm have to drop the lock while the mess around with breakpoints, but other archs avoid extra lock release/acquires in ptrace(). I did have to fix a couple of other consumers in kern_kse and a few other places to hold the proc lock and PHOLD. Tested by: ps (1 mostly, but some bits of 2-4 as well) MFC after: 1 week		2006-02-22 18:57:50 +00:00
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cd9660	I ran into an nfs client panic a couple of times in a row over the	2006-01-17 17:29:03 +00:00
coda	- Reorder calls to vrele() after calls to vput() when the vrele is a	2006-02-01 00:25:26 +00:00
deadfs	- Deadfs should not use the std GETWRITEMOUNT routine. Add one that always	2006-02-22 06:11:59 +00:00
devfs	- We must hold a reference to a vnode before calling vgone() otherwise	2006-02-22 09:05:40 +00:00
fdescfs	Normalize a significant number of kernel malloc type names:	2005-10-31 15:41:29 +00:00
fifofs	Second attempt at a work-around for fifo-related socket panics during	2005-10-01 20:15:41 +00:00
hpfs	I ran into an nfs client panic a couple of times in a row over the	2006-01-17 17:29:03 +00:00
msdosfs	- Reorder calls to vrele() after calls to vput() when the vrele is a	2006-02-01 00:25:26 +00:00
ntfs	I ran into an nfs client panic a couple of times in a row over the	2006-01-17 17:29:03 +00:00
nullfs	- spell VOP_LOCK(vp, LK_RELEASE... VOP_UNLOCK(vp,... so that asserts in	2006-02-22 06:17:31 +00:00
nwfs	I ran into an nfs client panic a couple of times in a row over the	2006-01-17 17:29:03 +00:00
portalfs	Normalize a significant number of kernel malloc type names:	2005-10-31 15:41:29 +00:00
procfs	Hold the proc lock while calling proc_sstep() since the function asserts	2006-02-22 17:20:37 +00:00
pseudofs	Close some races between procfs/ptrace and exit(2):	2006-02-22 18:57:50 +00:00
smbfs	I ran into an nfs client panic a couple of times in a row over the	2006-01-17 17:29:03 +00:00
udf	Make UDF endian-safe.	2006-02-03 15:25:52 +00:00
umapfs	Normalize a significant number of kernel malloc type names:	2005-10-31 15:41:29 +00:00
unionfs	Normalize a significant number of kernel malloc type names:	2005-10-31 15:41:29 +00:00