[Valgrind-developers] [valgrind] mips32: pass correct syscall value to kernel in case of __NR_syscall

[Petar J. <pe...@so...>]

https://sourceware.org/git/gitweb.cgi?p=valgrind.git;h=37f09ed248387ed3f4c7ba712fbc90e7468f6f4d

commit 37f09ed248387ed3f4c7ba712fbc90e7468f6f4d
Author: Petar Jovanovic <mip...@gm...>
Date:   Wed Apr 3 17:38:08 2019 +0000

    mips32: pass correct syscall value to kernel in case of __NR_syscall
    
    The syscall number has to be put in register v0 before call into the kernel.
    This was omitted when system call is __NR_syscall (and when the syscall
    argument is the system call number of interest).
    
    Patch by Nikola Milutinovic.

Diff:
---
 coregrind/m_syswrap/syscall-mips32-linux.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/coregrind/m_syswrap/syscall-mips32-linux.S b/coregrind/m_syswrap/syscall-mips32-linux.S
index 0bbfb2b..51f6518 100644
--- a/coregrind/m_syswrap/syscall-mips32-linux.S
+++ b/coregrind/m_syswrap/syscall-mips32-linux.S
@@ -112,7 +112,7 @@ ML_(do_syscall_for_client_WRK):
 
     lw $8, 48($29)    /* t0 == ThreadState */
 
-    lw $2, 52($29) /* v0 == syscallno */
+    lw $2, OFFSET_mips32_r2($8) /* v0 == guest_v0 */
     lw $4, OFFSET_mips32_r4($8)
     lw $5, OFFSET_mips32_r5($8)
     lw $6, OFFSET_mips32_r6($8)