d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

In cpu_fork(), initialize pcb_psl for the new process to PSL_KERNEL,

Browse Source 
instead of taking the (userland) eflags from the trap frame and masking
out PSL_I. There is no need to inherit any flags from the forking process;
the old method however can cause flags set in userland for the forking
process to be bogusly set in kernel mode when the newly forked process
runs for the first time (in particular PSL_T, which is set for userland
when the process is single-stepped; this would cause trace traps in
kernel mode).

Approved by:	re (jhb)
This commit is contained in:
Thomas Moestl 2003-05-16 01:10:33 +00:00
parent d98ae55eaf
commit a93b6bf5e9
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
sys/i386/i386/vm_machdep.c
View File

@ -181,7 +181,7 @@ cpu_fork(td1, p2, td2, flags)
pcb2->pcb_esp = (int)td2->td_frame - sizeof(void *);
pcb2->pcb_ebx = (int)td2; /* fork_trampoline argument */
pcb2->pcb_eip = (int)fork_trampoline;
pcb2->pcb_psl = td2->td_frame->tf_eflags & ~PSL_I; /* ints disabled */
pcb2->pcb_psl = PSL_KERNEL; /* ints disabled */
pcb2->pcb_gs = rgs();
/*-
* pcb2->pcb_dr*: cloned above.