RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-31 05:48:12 +00:00
Code Issues Activity Actions

Implement sending signals to blocked-in-kernel processes.

Browse source 
This is dirty but pretty cool! If we have a pending, unmasked signal for
a process that's blocked inside the kernel, we set up alternate stacks
for that process and unblock it to execute the signal handler.

A slightly different return trampoline is used here: since we need to
get back into the kernel, a dedicated syscall is used (sys$sigreturn.)

This restores the TSS contents of the process to the state it was in
while we were originally blocking in the kernel.

NOTE: There's currently only one "kernel resume TSS" so signal nesting
definitely won't work.
This commit is contained in:
Andreas Kling 2018-11-07 21:19:47 +01:00
parent c8b308910e
commit 03a8357e84
10 changed files with 190 additions and 27 deletions
Download patch file Download diff file Expand all files Collapse all files

6
Kernel/Syscall.cpp
View file

@ -54,7 +54,7 @@ static DWORD handle(RegisterDump& regs, DWORD function, DWORD arg1, DWORD arg2,
Console::the().putChar(arg1 & 0xff);
break;
case Syscall::SC_sleep:
return current->sys$sleep(arg1);
return current->sys$sleep((unsigned)arg1);
case Syscall::SC_gettimeofday:
return current->sys$gettimeofday((timeval*)arg1);
case Syscall::SC_spawn:
@ -156,6 +156,10 @@ static DWORD handle(RegisterDump& regs, DWORD function, DWORD arg1, DWORD arg2,
return current->sys$getgroups((int)arg1, (gid_t*)arg2);
case Syscall::SC_setgroups:
return current->sys$setgroups((size_t)arg1, (const gid_t*)arg2);
case Syscall::SC_sigreturn:
current->sys$sigreturn();
ASSERT_NOT_REACHED();
return 0;
default:
kprintf("<%u> int0x80: Unknown function %x requested {%x, %x, %x}\n", current->pid(), function, arg1, arg2, arg3);
break;