pmap_update() without calling pmap_enter().
(Probably calling only once after loop (as done in uvm_fault_lower_lookup())
is enough. If done so, other threads see entered neighbor pages as reflected
a little latter.)
numbers. Using ptoa() will cast to vaddr_t, which might no be adequate
for architectures where sizeof(paddr_t) > sizeof(vaddr_t) (like i386 PAE).
- small fix inside AGP heuristics to avoid masking high order bits for
systems with more than 4GB.
Reviewed by bouyer@.
See also http://mail-index.netbsd.org/tech-kern/2010/02/22/msg007373.html
This blocks an easy exploit of kernel bugs leading to dereference
of a NULL pointer on some architectures (eg i386).
The check can be disabled in various ways:
-by CPP definitions in machine/types.h (portmaster's choice)
-by a kernel config option USER_VA0_DISABLED_DEFAULT=0
-at runtime by sysctl vm.user_va0_disabled (cannot be cleared
at securelevel>0)
on the amount of physical memory and limited by NMBCLUSTERS if present.
Architectures without direct mapping also limit it based on the kmem_map
size, which is used as backing store. On i386 and ARM, the maximum KVA
used for mbuf clusters is limited to 64MB by default.
The old default limits and limits based on GATEWAY have been removed.
key_registered_sb_max is hard-wired to a value derived from 2048
clusters.
refers to another "uobj" used to call pgo_get. Revert the wrong assertion
I made. My bad.
(This and pgo_get's possible ERESTART return value check is the only 2 behavioral
changes I made.)
Reported by drochner@, thanks.
- Lower fault routines don't care the vm_anon array found in upper lookup.
Don't pass the pointer down.
- The flag "shadowed" is known when we lookup upper layer. Don't need to
keep in the fault context struct.
the original values. Pointed out by rmind@, thanks.
In the lower fault case, if (*pgo_get)() can return ERESTART and we should
re-fault for that remains a question. The original code just returned the
error, so keep that behaviour for now. In case (*pgo_get)() really returns
ERESTART, pass EIO to tell the uvm_fault caller that (*pgo_get)() failed.
(As far as I grep callers don't check if the return value is ERESTART or not.
So assuming (*pgo_get)() never returns ERESTART should be a safe bet.)
Move local variables around to isolate contexts. Note that remaining variables
are global in that function, and some hold state across re-fault.
Slilently clean-up the "eoff" mess.
(Superfluous braces will go once things settle down.)
