* Dave Hansen <[email protected]> wrote: > > We do not have tracepoints for sys_modify_ldt() because we define > it directly instead of using the normal SYSCALL_DEFINEx() macros. > > However, there is a reason sys_modify_ldt() does not use the macros: > it has an 'int' return type instead of 'unsigned long'. This is > a bug, but it's a bug cemented in the ABI. > > What does this mean? If we return -EINVAL from a function that > returns 'int', we have 0x00000000ffffffea in %rax. But, if we > return -EINVAL from a function returning 'unsigned long', we end > up with 0xffffffffffffffea in %rax, which is wrong. > > To work around this and maintain the 'int' behavior while using > the SYSCALL_DEFINEx() macros, so we add a cast to 'unsigned int' > in both implementations of sys_modify_ldt(). > > Cc: [email protected] > Cc: Andy Lutomirski <[email protected]> > Cc: Brian Gerst <[email protected]>
I have added your: Signed-off-by: Dave Hansen <[email protected]> let me know if that's OK. Thanks, Ingo
