private to the process within the share group.
There is one bit missing in this implementation: when replicating a change
in a process VM to the other process of the share group, we avoid copying
mappings for private regions in the target process, but we don't prevent
copying private regions from the source process.
it actually fixes a problem:
When /bin/sh gets a SIGSEGV, its signal handler calls brk and the offending
instruction is retried. Usually it gets another SIGSEGV, and things loops
until it pases without the SIGSEGV. This is the normal mode of operation, and
it can be reproduced on IRIX by a 10kB shell script starting by echo /*
However... the signal handler checks for BADVADDR in the saved registers
in struct sigcontext. If it does not find it, it gives up and exit instead
of retrying. Filling the field enables us to carry on normal operation
(which is to get dozens of SIGSEGV) instead of getting a failure at the
first SIGSEGV.
there's an error. Store the result of this function in a signed
variable instead of an unsigned variable before checking if the return
value is greater than zero.
memory fault handler. IRIX uses irix_vm_fault, and all other emulation
use NULL, which means to use uvm_fault.
- While we are there, explicitely set to NULL the uninitialized fields in
struct emul: e_fault and e_sysctl on most ports
- e_fault is used by the trap handler, for now only on mips. In order to avoid
intrusive modifications in UVM, the function pointed by e_fault does not
has exactly the same protoype as uvm_fault:
int uvm_fault __P((struct vm_map *, vaddr_t, vm_fault_t, vm_prot_t));
int e_fault __P((struct proc *, vaddr_t, vm_fault_t, vm_prot_t));
- In IRIX share groups, all the VM space is shared, except one page.
This bounds us to have different VM spaces and synchronize modifications
to the VM space accross share group members. We need an IRIX specific hook
to the page fault handler in order to propagate VM space modifications
caused by page faults.
This merge changes the device switch tables from static array to
dynamically generated by config(8).
- All device switches is defined as a constant structure in device drivers.
- The new grammer ``device-major'' is introduced to ``files''.
device-major <prefix> char <num> [block <num>] [<rules>]
- All device major numbers must be listed up in port dependent majors.<arch>
by using this grammer.
- Added the new naming convention.
The name of the device switch must be <prefix>_[bc]devsw for auto-generation
of device switch tables.
- The backward compatibility of loading block/character device
switch by LKM framework is broken. This is necessary to convert
from block/character device major to device name in runtime and vice versa.
- The restriction to assign device major by LKM is completely removed.
We don't need to reserve LKM entries for dynamic loading of device switch.
- In compile time, device major numbers list is packed into the kernel and
the LKM framework will refer it to assign device major number dynamically.
usync_cntl() system calls.
- when usync_cntl is used and the process is aborted (eg: by kill -9)
libc does not call usync_cntl() to unblock things. We have to cleanup
data allocated in the kernel. This is now done through the emulation
specific exit hook
- IRIX initialize some data in the system part of the PRDA: the pid and
a prid (PRDA ID?). We initialize both to pid.
- Move back struct irix_share_group from irix_exec.h to irix_prctl.h, it
is more revelant here.
- fix a few typos
gets reset properly when the old parent exits before the child. A flag
is set in old parent process when the child is reparented in ptrace(2).
If it's set when process is exiting, all running processes have their
'old parent process' pointer checked and reset if appropriate. Also
change to use 'struct proc *' pointer directly, rather than pid_t.
This fixes security/14444 by David Sainty.
Reviewed by Christos Zoulas.
manu