On 8/28/05, Yagnavarahan <yagnavarahan@xxxxxxxxx> wrote: > >I am assuming you know this is essentially a "hack" and should be done > >for educational purposes only. > > I'm only trying to hook onto syscalls now that 2.6 doesn't export the > syscall table. Modifying the syscall table, I believe was a very fragile > technique but with modifying the IDT, If proper synchronization is in place, > why would it fail? How can you get hold of a system call by modifing the IDT. AFAIK, IDT is the entry point for interrupts routines not for system call functions. Well in anycase if you want to modify the IDT, do use some mechanisum thru which you can disable the interrupts on all CPUs. Well I dont know if there is some kernel function which can do this or not. Well after doing some googling on net, I found IBM's article related to changes in 2.6 kernel, in this article there is a section interuupt handling also, here is a small text from that section " Note that cli(), sti(), save_flags(), and restore_flags() are all deprecated. Instead, local_save_flags() and local_irq_disable() should be used to disable all interrupts locally (within that processor). It is not possible to disable interrupts across all processors." To have a look at full article, visit : http://www-128.ibm.com/developerworks/linux/library/l-inside.html regards. -Gaurav > > Thanks, > YV > > > -- > Kernelnewbies: Help each other learn about the Linux kernel. > Archive: http://mail.nl.linux.org/kernelnewbies/ > FAQ: http://kernelnewbies.org/faq/ > > -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
