On Mon, Oct 16, 2017 at 01:14:54PM +0100, Ard Biesheuvel wrote: > On 16 October 2017 at 12:42, Liuwenliang (Lamb) <liuwenliang@xxxxxxxxxx> wrote: > > On 10/16/2017 07:03 PM, Abbott Liu wrote: > >>arch/arm/kernel/entry-armv.S:348: Error: selected processor does not support `movw r1, > > #:lower16:((((0xC0000000-0x01000000)>>3)+((0xC0000000-0x01000000)-(1<<29))))' in ARM mode > >>arch/arm/kernel/entry-armv.S:348: Error: selected processor does not support `movt r1, > > #:upper16:((((0xC0000000-0x01000000)>>3)+((0xC0000000-0x01000000)-(1<<29))))' in ARM mode > > > > Thanks for building test. This error can be solved by following code: > > --- a/arch/arm/kernel/entry-armv.S > > +++ b/arch/arm/kernel/entry-armv.S > > @@ -188,8 +188,7 @@ ENDPROC(__und_invalid) > > get_thread_info tsk > > ldr r0, [tsk, #TI_ADDR_LIMIT] > > #ifdef CONFIG_KASAN > > - movw r1, #:lower16:TASK_SIZE > > - movt r1, #:upper16:TASK_SIZE > > + ldr r1, =TASK_SIZE > > #else > > mov r1, #TASK_SIZE > > #endif > > This is unnecessary: > > ldr r1, =TASK_SIZE > > will be converted to a mov instruction by the assembler if the value > of TASK_SIZE fits its 12-bit immediate field. It's an 8-bit immediate field for ARM. What it won't do is expand it to a pair of movw/movt instructions if it doesn't fit. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up According to speedtest.net: 8.21Mbps down 510kbps up -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
