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-rw-r--r--kernel/arch/arm64/kernel/entry.S61
1 files changed, 32 insertions, 29 deletions
diff --git a/kernel/arch/arm64/kernel/entry.S b/kernel/arch/arm64/kernel/entry.S
index 6515be375..dd8fd31f8 100644
--- a/kernel/arch/arm64/kernel/entry.S
+++ b/kernel/arch/arm64/kernel/entry.S
@@ -21,7 +21,7 @@
#include <linux/init.h>
#include <linux/linkage.h>
-#include <asm/alternative-asm.h>
+#include <asm/alternative.h>
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/cpufeature.h>
@@ -116,38 +116,34 @@
*/
.endm
- .macro kernel_exit, el, ret = 0
+ .macro kernel_exit, el
ldp x21, x22, [sp, #S_PC] // load ELR, SPSR
.if \el == 0
ct_user_enter
ldr x23, [sp, #S_SP] // load return stack pointer
msr sp_el0, x23
-
#ifdef CONFIG_ARM64_ERRATUM_845719
- alternative_insn \
- "nop", \
- "tbz x22, #4, 1f", \
- ARM64_WORKAROUND_845719
+alternative_if_not ARM64_WORKAROUND_845719
+ nop
+ nop
+#ifdef CONFIG_PID_IN_CONTEXTIDR
+ nop
+#endif
+alternative_else
+ tbz x22, #4, 1f
#ifdef CONFIG_PID_IN_CONTEXTIDR
- alternative_insn \
- "nop; nop", \
- "mrs x29, contextidr_el1; msr contextidr_el1, x29; 1:", \
- ARM64_WORKAROUND_845719
+ mrs x29, contextidr_el1
+ msr contextidr_el1, x29
#else
- alternative_insn \
- "nop", \
- "msr contextidr_el1, xzr; 1:", \
- ARM64_WORKAROUND_845719
+ msr contextidr_el1, xzr
#endif
+1:
+alternative_endif
#endif
.endif
msr elr_el1, x21 // set up the return data
msr spsr_el1, x22
- .if \ret
- ldr x1, [sp, #S_X1] // preserve x0 (syscall return)
- .else
ldp x0, x1, [sp, #16 * 0]
- .endif
ldp x2, x3, [sp, #16 * 1]
ldp x4, x5, [sp, #16 * 2]
ldp x6, x7, [sp, #16 * 3]
@@ -349,8 +345,8 @@ el1_inv:
// TODO: add support for undefined instructions in kernel mode
enable_dbg
mov x0, sp
+ mov x2, x1
mov x1, #BAD_SYNC
- mrs x2, esr_el1
b bad_mode
ENDPROC(el1_sync)
@@ -440,6 +436,8 @@ el0_sync_compat:
b.eq el0_fpsimd_acc
cmp x24, #ESR_ELx_EC_FP_EXC32 // FP/ASIMD exception
b.eq el0_fpsimd_exc
+ cmp x24, #ESR_ELx_EC_PC_ALIGN // pc alignment exception
+ b.eq el0_sp_pc
cmp x24, #ESR_ELx_EC_UNKNOWN // unknown exception in EL0
b.eq el0_undef
cmp x24, #ESR_ELx_EC_CP15_32 // CP15 MRC/MCR trap
@@ -556,7 +554,7 @@ el0_inv:
ct_user_exit
mov x0, sp
mov x1, #BAD_SYNC
- mrs x2, esr_el1
+ mov x2, x25
bl bad_mode
b ret_to_user
ENDPROC(el0_sync)
@@ -588,7 +586,8 @@ 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
@@ -597,7 +596,7 @@ 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
@@ -615,17 +614,21 @@ ENDPROC(cpu_switch_to)
*/
ret_fast_syscall:
disable_irq // disable interrupts
- ldr x1, [tsk, #TI_FLAGS]
+ str x0, [sp, #S_X0] // returned x0
+ ldr x1, [tsk, #TI_FLAGS] // re-check for syscall tracing
+ and x2, x1, #_TIF_SYSCALL_WORK
+ cbnz x2, ret_fast_syscall_trace
and x2, x1, #_TIF_WORK_MASK
- cbnz x2, fast_work_pending
+ cbnz x2, work_pending
enable_step_tsk x1, x2
- kernel_exit 0, ret = 1
+ kernel_exit 0
+ret_fast_syscall_trace:
+ enable_irq // enable interrupts
+ b __sys_trace_return_skipped // we already saved x0
/*
* Ok, we need to do extra processing, enter the slow path.
*/
-fast_work_pending:
- str x0, [sp, #S_X0] // returned x0
work_pending:
tbnz x1, #TIF_NEED_RESCHED, work_resched
tbnz x1, #TIF_NEED_RESCHED_LAZY, work_resched
@@ -650,7 +653,7 @@ ret_to_user:
cbnz x2, work_pending
enable_step_tsk x1, x2
no_work_pending:
- kernel_exit 0, ret = 0
+ kernel_exit 0
ENDPROC(ret_to_user)
/*