window_ret_fault on SPARC

From: Baurjan Ismagulov (
Date: Wed Oct 10 2001 - 16:41:43 EST


my kernel gets into window_ret_fault while returning from trap to
user mode.

In the trap return code, SRMMU sets "Fault Address Valid" during
"save; LOAD_WINDOW(sp); restore". After that, SFSR=00000127 and
SFAR=efffed18. Loaded %fp value is efffece0, and [efffece0+38]
contains efffed50 -- at least, that is what I see in kgdb using "p/x
*(struct reg_window *)0xefffece0". I also tried to see that using
printk from window_ret_fault, but the kernel hung solidly (L1-A didn't

I followed all vm_next links in current->mm->mmap; efffd000-effff000
area seems to be there. However, I was unable to track it via


1. Why do I get multiple (SFSR.OV=1) faults in srmmu_rett_stackchk?

2. How can I see whether page directories of the current process are
   set up correctly?

I would be very grateful if someone could help me to solve this problem. I'm using 2.2.19 on sun4m.

Thanks in advance,
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

This archive was generated by hypermail 2b29 : Mon Oct 15 2001 - 21:00:35 EST