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authorRobert Morris <[email protected]>2022-08-22 13:49:15 -0400
committerRobert Morris <[email protected]>2022-08-22 13:49:15 -0400
commit63ef3b8c9fd15d5ea5775813cda94a3c64cff0d3 (patch)
tree13a80865f2ef47967f19777bb57e7632dfc73247 /kernel/trap.c
parentf2ee8690addf0aa52b5de2061fe6d659574406f9 (diff)
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slightly better comments
Diffstat (limited to 'kernel/trap.c')
-rw-r--r--kernel/trap.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/kernel/trap.c b/kernel/trap.c
index 75fb3ec..524da44 100644
--- a/kernel/trap.c
+++ b/kernel/trap.c
@@ -60,8 +60,8 @@ usertrap(void)
// but we want to return to the next instruction.
p->trapframe->epc += 4;
- // an interrupt will change sstatus &c registers,
- // so don't enable until done with those registers.
+ // an interrupt will change sepc, scause, and sstatus,
+ // so enable only now that we're done with those registers.
intr_on();
syscall();
@@ -101,7 +101,7 @@ usertrapret(void)
w_stvec(trampoline_uservec);
// set up trapframe values that uservec will need when
- // the process next re-enters the kernel.
+ // the process next traps into the kernel.
p->trapframe->kernel_satp = r_satp(); // kernel page table
p->trapframe->kernel_sp = p->kstack + PGSIZE; // process's kernel stack
p->trapframe->kernel_trap = (uint64)usertrap;