John Baldwin wrote:
>
> On 22-Nov-2002 Juli Mallett wrote:
> > * De: Robert Watson <[EMAIL PROTECTED]> [ Data: 2002-11-21 ]
> > [ Subjecte: Re: VM locking problem... And doscmd(8) ]
> >> On Thu, 21 Nov 2002, Juli Mallett wrote:
> >>
> >> > I'm getting a giant owned assertion failure in the vm_map code, simply
> >> > by running "doscmd something.exe" where something.exe is a
> >> > self-extracting ZIP file (of BIOS upgrade stuff, FWIW), which leads
> >> > trivially to tripping over it. I still don't have a good way to get the
> >> > trace output from the box in question to here, but I've been able to
> >> > reproduce it every time, so it shouldn't be hard for someone else.
> >> >
> >> > I rebuilt my kernel today from CVSup, but hadn't tried before that.
> >>
> >> For those of us that don't frequently (ever) use doscmd -- can you provide
> >> a tarball of the necessary configuration files, executable, etc,
> >> somewhere?
> >
> > I don't (ever) either, and am doing this without a config file (as far as
> > I'm aware anyway), and using the following executable:
> >
> > http://people.freebsd.org/~jmallett/boom.exe
>
> There is some discussion on IRC, and Maxime is working on a fix. The
> problem is that if you use a TSS (for /dev/io or some such) then the
> TSS gets kmem_free()'d in cpu_thread_exit(). However, cpu_thread_exit()
> is a particularly bad time to be calling kmem_free() as you are holding
> sched_lock in a critical section w/o any sleep mutexes when it is called.
> :) The solution I've discussed with Maxime is to create a
> cpu_thread_dtor() callout called from thread_dtor() (which is called when
> a thread is free()'d) and to move the kmem_free() of the TSS into
> that function instead.
The attached patch fixes it for me. It free()'s the TSS in the new
cpu_thread_dtor() function as John suggested.
Cheers,
Maxime
Index: kern/kern_thread.c
===================================================================
RCS file: /space2/ncvs/src/sys/kern/kern_thread.c,v
retrieving revision 1.65
diff -u -p -r1.65 kern_thread.c
--- kern/kern_thread.c 21 Nov 2002 01:22:38 -0000 1.65
+++ kern/kern_thread.c 22 Nov 2002 16:40:16 -0000
@@ -115,6 +115,7 @@ thread_dtor(void *mem, int size, void *a
{
struct thread *td;
+ mtx_assert(&Giant, MA_OWNED);
td = (struct thread *)mem;
#ifdef INVARIANTS
@@ -137,6 +138,8 @@ thread_dtor(void *mem, int size, void *a
/* NOTREACHED */
}
#endif
+
+ cpu_thread_dtor(td);
}
/*
Index: sys/proc.h
===================================================================
RCS file: /space2/ncvs/src/sys/sys/proc.h,v
retrieving revision 1.282
diff -u -p -r1.282 proc.h
--- sys/proc.h 21 Nov 2002 09:14:12 -0000 1.282
+++ sys/proc.h 22 Nov 2002 16:21:52 -0000
@@ -905,6 +905,7 @@ void kse_free(struct kse *ke);
void kse_stash(struct kse *ke);
void cpu_set_upcall(struct thread *td, void *pcb);
void cpu_set_upcall_kse(struct thread *td, struct kse *ke);
+void cpu_thread_dtor(struct thread *);
void cpu_thread_exit(struct thread *);
void cpu_thread_setup(struct thread *td);
void kse_reassign(struct kse *ke);
Index: i386/i386/vm_machdep.c
===================================================================
RCS file: /space2/ncvs/src/sys/i386/i386/vm_machdep.c,v
retrieving revision 1.193
diff -u -p -r1.193 vm_machdep.c
--- i386/i386/vm_machdep.c 9 Oct 2002 02:33:35 -0000 1.193
+++ i386/i386/vm_machdep.c 22 Nov 2002 16:42:51 -0000
@@ -272,24 +272,32 @@ cpu_thread_exit(struct thread *td)
#ifdef DEV_NPX
npxexit(td);
#endif
+ if (pcb->pcb_flags & PCB_DBREGS) {
+ /*
+ * disable all hardware breakpoints
+ */
+ reset_dbregs();
+ pcb->pcb_flags &= ~PCB_DBREGS;
+ }
+}
+
+void
+cpu_thread_dtor(struct thread *td)
+{
+ struct pcb *pcb;
+
+ pcb = td->td_pcb;
if (pcb->pcb_ext != 0) {
/* XXXKSE XXXSMP not SMP SAFE.. what locks do we have? */
/* if (pcb->pcb_ext->ext_refcount-- == 1) ?? */
- /*
- * XXX do we need to move the TSS off the allocated pages
+ /*
+ * XXX do we need to move the TSS off the allocated pages
* before freeing them? (not done here)
*/
kmem_free(kernel_map, (vm_offset_t)pcb->pcb_ext,
ctob(IOPAGES + 1));
pcb->pcb_ext = 0;
}
- if (pcb->pcb_flags & PCB_DBREGS) {
- /*
- * disable all hardware breakpoints
- */
- reset_dbregs();
- pcb->pcb_flags &= ~PCB_DBREGS;
- }
}
void
Index: alpha/alpha/vm_machdep.c
===================================================================
RCS file: /space2/ncvs/src/sys/alpha/alpha/vm_machdep.c,v
retrieving revision 1.74
diff -u -p -r1.74 vm_machdep.c
--- alpha/alpha/vm_machdep.c 23 Sep 2002 08:04:30 -0000 1.74
+++ alpha/alpha/vm_machdep.c 22 Nov 2002 16:24:48 -0000
@@ -261,6 +261,11 @@ cpu_thread_exit(struct thread *td)
}
void
+cpu_thread_dtor(struct thread *td)
+{
+}
+
+void
cpu_thread_setup(struct thread *td)
{
Index: ia64/ia64/vm_machdep.c
===================================================================
RCS file: /space2/ncvs/src/sys/ia64/ia64/vm_machdep.c,v
retrieving revision 1.48
diff -u -p -r1.48 vm_machdep.c
--- ia64/ia64/vm_machdep.c 30 Oct 2002 05:55:29 -0000 1.48
+++ ia64/ia64/vm_machdep.c 22 Nov 2002 16:43:45 -0000
@@ -118,6 +118,11 @@ cpu_thread_exit(struct thread *td)
}
void
+cpu_thread_dtor(struct thread *td)
+{
+}
+
+void
cpu_thread_setup(struct thread *td)
{
}
Index: powerpc/powerpc/vm_machdep.c
===================================================================
RCS file: /space2/ncvs/src/sys/powerpc/powerpc/vm_machdep.c,v
retrieving revision 1.77
diff -u -p -r1.77 vm_machdep.c
--- powerpc/powerpc/vm_machdep.c 21 Oct 2002 05:27:41 -0000 1.77
+++ powerpc/powerpc/vm_machdep.c 22 Nov 2002 16:44:37 -0000
@@ -354,6 +354,11 @@ cpu_thread_exit(struct thread *td)
}
void
+cpu_thread_dtor(struct thread *td)
+{
+}
+
+void
cpu_thread_setup(struct thread *td)
{
Index: sparc64/sparc64/vm_machdep.c
===================================================================
RCS file: /space2/ncvs/src/sys/sparc64/sparc64/vm_machdep.c,v
retrieving revision 1.27
diff -u -p -r1.27 vm_machdep.c
--- sparc64/sparc64/vm_machdep.c 17 Sep 2002 16:21:48 -0000 1.27
+++ sparc64/sparc64/vm_machdep.c 22 Nov 2002 16:23:32 -0000
@@ -114,6 +114,11 @@ cpu_thread_exit(struct thread *td)
}
void
+cpu_thread_dtor(struct thread *td)
+{
+}
+
+void
cpu_thread_setup(struct thread *td)
{
}
