From c0d3fce5e192c6b45a9d8e06aecfcec546f73884 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 20 Jul 2015 15:14:53 +0100 Subject: [PATCH] arm64: switch_to: calculate cpu context pointer using separate register Commit 0c8c0f03e3a2 ("x86/fpu, sched: Dynamically allocate 'struct fpu'") moved the thread_struct to the bottom of task_struct. As a result, the offset is now too large to be used in an immediate add on arm64 with some kernel configs: arch/arm64/kernel/entry.S: Assembler messages: arch/arm64/kernel/entry.S:588: Error: immediate out of range arch/arm64/kernel/entry.S:597: Error: immediate out of range This patch calculates the offset using an additional register instead of an immediate offset. Fixes: 0c8c0f03e3a2 ("x86/fpu, sched: Dynamically allocate 'struct fpu'") Cc: Dave Hansen Cc: Olof Johansson Cc: Ingo Molnar Signed-off-by: Will Deacon Tested-by: Guenter Roeck Signed-off-by: Catalin Marinas --- arch/arm64/kernel/entry.S | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index f860bfda454a..e16351819fed 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -585,7 +585,8 @@ ENDPROC(el0_irq) * */ ENTRY(cpu_switch_to) - add x8, x0, #THREAD_CPU_CONTEXT + mov x10, #THREAD_CPU_CONTEXT + add x8, x0, x10 mov x9, sp stp x19, x20, [x8], #16 // store callee-saved registers stp x21, x22, [x8], #16 @@ -594,7 +595,7 @@ ENTRY(cpu_switch_to) stp x27, x28, [x8], #16 stp x29, x9, [x8], #16 str lr, [x8] - add x8, x1, #THREAD_CPU_CONTEXT + add x8, x1, x10 ldp x19, x20, [x8], #16 // restore callee-saved registers ldp x21, x22, [x8], #16 ldp x23, x24, [x8], #16 -- 2.39.2