On Fri, Sep 18, 2020 at 02:46:15PM +0200, Arnd Bergmann wrote: > Hi Christoph, Russell, > > Here is an updated series for removing set_fs() from arch/arm, > based on the previous feedback. > > I have tested the oabi-compat changes using the LTP tests for the three > modified syscalls using an Armv7 kernel and a Debian 5 OABI user space, > and I have lightly tested the get_kernel_nofault infrastructure by > loading the test_lockup.ko module after setting CONFIG_DEBUG_SPINLOCK. I'm not too keen on always saving the syscall number, but for the gain of getting rid of set_fs() I think it's worth it. However... I think there are some things to check - what value do you end up with as the first number in /proc/self/syscall when you do: strace cat /proc/self/syscall ? It should be 3, not 0x900003. I suspect you're getting the latter with these changes. IIRC, task_thread_info(task)->syscall needs to be the value _without_ the offset, otherwise tracing will break. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!