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Now that we have the signal trampolines in the gateway page and the

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gateway page is considered kernel space, we can panic when we should
only SIGSEGV. Hence, add the additional constraint that for page
faults we also require running with kernel privileges. The gateway
page is the only kernel code running with user privileges, iso this
is a correct way to exclude the gateway page from kernel land.

We do not currently exclude the gateway page for other faults as it
is not always the right way to do it. Further tuning will happen on
a case by case bases.
This commit is contained in:
Marcel Moolenaar 2003-05-31 21:21:35 +00:00
parent 89e50d0e9a
commit 5e7019bf32
1 changed files with 7 additions and 1 deletions
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8
sys/ia64/ia64/trap.c
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@ -696,7 +696,13 @@ trap(int vector, struct trapframe *framep)
goto out;
no_fault_in:
if (!user) {
/*
* Additionally check the privilege level. We don't want to
* panic when we're in the gateway page, running at user
* level.
*/
if (!user && (framep->tf_special.psr & IA64_PSR_CPL)
== IA64_PSR_CPL_KERN) {
/* Check for copyin/copyout fault. */
if (td != NULL && td->td_pcb->pcb_onfault != 0) {
framep->tf_special.iip =