diff options
| -rw-r--r-- | arch/xtensa/kernel/entry.S | 43 |
1 files changed, 28 insertions, 15 deletions
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index 51e9877ced06..e955f6098f64 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -122,6 +122,7 @@ _user_exception: /* Save SAR and turn off single stepping */ movi a2, 0 + wsr a2, depc # terminate user stack trace with 0 rsr a3, sar xsr a2, icountlevel s32i a3, a1, PT_SAR @@ -301,7 +302,18 @@ _kernel_exception: s32i a14, a1, PT_AREG14 s32i a15, a1, PT_AREG15 + _bnei a2, 1, 1f + + /* Copy spill slots of a0 and a1 to imitate movsp + * in order to keep exception stack continuous + */ + l32i a3, a1, PT_SIZE + l32i a0, a1, PT_SIZE + 4 + s32e a3, a1, -16 + s32e a0, a1, -12 1: + l32i a0, a1, PT_AREG0 # restore saved a0 + wsr a0, depc #ifdef KERNEL_STACK_OVERFLOW_CHECK @@ -346,12 +358,12 @@ common_exception: s32i a0, a1, PT_EXCCAUSE s32i a3, a2, EXC_TABLE_FIXUP - /* All unrecoverable states are saved on stack, now, and a1 is valid, - * so we can allow exceptions and interrupts (*) again. - * Set PS(EXCM = 0, UM = 0, RING = 0, OWB = 0, WOE = 1, INTLEVEL = X) + /* All unrecoverable states are saved on stack, now, and a1 is valid. + * Now we can allow exceptions again. In case we've got an interrupt + * PS.INTLEVEL is set to LOCKLEVEL disabling furhter interrupts, + * otherwise it's left unchanged. * - * (*) We only allow interrupts if they were previously enabled and - * we're not handling an IRQ + * Set PS(EXCM = 0, UM = 0, RING = 0, OWB = 0, WOE = 1, INTLEVEL = X) */ rsr a3, ps @@ -362,28 +374,30 @@ common_exception: moveqz a3, a2, a0 # a3 = LOCKLEVEL iff interrupt movi a2, 1 << PS_WOE_BIT or a3, a3, a2 - rsr a0, exccause + rsr a2, exccause + /* restore return address (or 0 if return to userspace) */ + rsr a0, depc xsr a3, ps s32i a3, a1, PT_PS # save ps /* Save lbeg, lend */ - rsr a2, lbeg + rsr a4, lbeg rsr a3, lend - s32i a2, a1, PT_LBEG + s32i a4, a1, PT_LBEG s32i a3, a1, PT_LEND /* Save SCOMPARE1 */ #if XCHAL_HAVE_S32C1I - rsr a2, scompare1 - s32i a2, a1, PT_SCOMPARE1 + rsr a3, scompare1 + s32i a3, a1, PT_SCOMPARE1 #endif /* Save optional registers. */ - save_xtregs_opt a1 a2 a4 a5 a6 a7 PT_XTREGS_OPT + save_xtregs_opt a1 a3 a4 a5 a6 a7 PT_XTREGS_OPT #ifdef CONFIG_TRACE_IRQFLAGS l32i a4, a1, PT_DEPC @@ -391,8 +405,7 @@ common_exception: * while PS.EXCM was set, i.e. interrupts disabled. */ bgeui a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 1f - l32i a4, a1, PT_EXCCAUSE - bnei a4, EXCCAUSE_LEVEL1_INTERRUPT, 1f + bnei a2, EXCCAUSE_LEVEL1_INTERRUPT, 1f /* We came here with an interrupt means interrupts were enabled * and we've just disabled them. */ @@ -407,8 +420,8 @@ common_exception: rsr a4, excsave1 mov a6, a1 # pass stack frame - mov a7, a0 # pass EXCCAUSE - addx4 a4, a0, a4 + mov a7, a2 # pass EXCCAUSE + addx4 a4, a2, a4 l32i a4, a4, EXC_TABLE_DEFAULT # load handler /* Call the second-level handler */ |