diff options
| author | dzwdz | 2021-07-23 13:50:00 +0200 |
|---|---|---|
| committer | dzwdz | 2021-07-23 13:50:00 +0200 |
| commit | 8a29c78d34f1924c4e39a3a951b36c4512ffe9c1 (patch) | |
| tree | 624319a6dd15593be381c48d03ef5c8b568020a0 | |
| parent | 91c637d847744ba410cbf0e20c62c485e1f6153d (diff) | |
update the process' EIP/ESP when it syscalls
| -rw-r--r-- | src/kernel/arch/generic.h | 2 | ||||
| -rw-r--r-- | src/kernel/arch/i386/sysenter.s | 8 | ||||
| -rw-r--r-- | src/kernel/syscalls.c | 5 |
3 files changed, 10 insertions, 5 deletions
diff --git a/src/kernel/arch/generic.h b/src/kernel/arch/generic.h index 6200320..8db079c 100644 --- a/src/kernel/arch/generic.h +++ b/src/kernel/arch/generic.h @@ -17,7 +17,7 @@ void halt_cpu(); // src/arch/i386/sysenter.s void sysexit(void (*fun)(), void *stack_top); void sysenter_setup(); -int syscall_handler(int, int, int, int); +int syscall_handler(int, int, int, int, void *stack, void *eip); // all of those can allocate memory struct pagedir *pagedir_new(); diff --git a/src/kernel/arch/i386/sysenter.s b/src/kernel/arch/i386/sysenter.s index 7375e06..64b7d01 100644 --- a/src/kernel/arch/i386/sysenter.s +++ b/src/kernel/arch/i386/sysenter.s @@ -49,6 +49,8 @@ sysenter_setup: sysenter_handler: pushal + push %edx + push %ecx push %edi push %esi push %ebx @@ -61,13 +63,13 @@ sysenter_handler: call syscall_handler // save the return value - mov %eax, 44(%esp) // 16 [top of eflags] + 7*4 [skip until EAX] - mov %edx, 32(%esp) // 16 + 4*4 [skip until EBX] + mov %eax, 52(%esp) // 24 [top of eflags] + 7*4 [skip until EAX] + mov %edx, 40(%esp) // 24 + 4*4 [skip until EBX] mov %cr0, %eax or $0x80000000, %eax // enable paging mov %eax, %cr0 - add $16, %esp + add $24, %esp popal sysexit diff --git a/src/kernel/syscalls.c b/src/kernel/syscalls.c index 2af8cf9..24706d3 100644 --- a/src/kernel/syscalls.c +++ b/src/kernel/syscalls.c @@ -18,7 +18,10 @@ int sc_debuglog(const char *msg, size_t len) { return len; } -int syscall_handler(int num, int a, int b, int c) { +int syscall_handler(int num, int a, int b, int c, void *stack, void *eip) { + process_current->esp = stack; + process_current->eip = eip; + switch (num) { case SC_DEBUGLOG: return sc_debuglog((void*)a, b); |