generic-library/bionic
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Merge "Fix _exit_with_stack_teardown for x86."

Browse Source
This commit is contained in:
Elliott Hughes 2013-11-26 21:51:48 +00:00 committed by Gerrit Code Review
commit 1c057607d8
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
libc/arch-x86/bionic/_exit_with_stack_teardown.S
View File

@ -3,12 +3,13 @@
// void _exit_with_stack_teardown(void* stackBase, size_t stackSize, int status) // void _exit_with_stack_teardown(void* stackBase, size_t stackSize, int status)
ENTRY(_exit_with_stack_teardown) ENTRY(_exit_with_stack_teardown)
// We can trash %ebx here since this call should never return. // We can trash registers because this function never returns.
// We can also take advantage of the fact that the linux syscall trap // We can also take advantage of the fact that the linux syscall trap
// handler saves all the registers, so we don't need a stack to keep // handler saves all the registers, so we don't need a stack to keep
// the status argument for exit while doing the munmap. // the status argument for exit while doing the munmap.
mov 4(%esp), %ebx // stackBase mov 4(%esp), %ebx // stackBase
mov 8(%esp), %ecx // stackSize mov 8(%esp), %ecx // stackSize
mov 12(%esp), %edx // Also copy 'status' off the stack we're about to unmap.
mov $__NR_munmap, %eax mov $__NR_munmap, %eax
int $0x80 int $0x80
// If munmap failed, we ignore the failure and exit anyway. // If munmap failed, we ignore the failure and exit anyway.