#include <asm/asm-uaccess.h>
#include <asm/unistd.h>
-/*
- * Context tracking and irqflag tracing need to instrument transitions between
- * user and kernel mode.
- */
- .macro user_enter_irqoff
-#if defined(CONFIG_CONTEXT_TRACKING) || defined(CONFIG_TRACE_IRQFLAGS)
- bl exit_to_user_mode
-#endif
- .endm
-
.macro clear_gp_regs
.irp n,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29
mov x\n, xzr
.endm
/* Check for MTE asynchronous tag check faults */
- .macro check_mte_async_tcf, tmp, ti_flags
+ .macro check_mte_async_tcf, tmp, ti_flags, thread_sctlr
#ifdef CONFIG_ARM64_MTE
.arch_extension lse
alternative_if_not ARM64_MTE
b 1f
alternative_else_nop_endif
+ /*
+ * Asynchronous tag check faults are only possible in ASYNC (2) or
+ * ASYM (3) modes. In each of these modes bit 1 of SCTLR_EL1.TCF0 is
+ * set, so skip the check if it is unset.
+ */
+ tbz \thread_sctlr, #(SCTLR_EL1_TCF0_SHIFT + 1), 1f
mrs_s \tmp, SYS_TFSRE0_EL1
tbz \tmp, #SYS_TFSR_EL1_TF0_SHIFT, 1f
/* Asynchronous TCF occurred for TTBR0 access, set the TI flag */
mov \tmp, #_TIF_MTE_ASYNC_FAULT
add \ti_flags, tsk, #TSK_TI_FLAGS
stset \tmp, [\ti_flags]
- msr_s SYS_TFSRE0_EL1, xzr
1:
#endif
.endm
/* Clear the MTE asynchronous tag check faults */
- .macro clear_mte_async_tcf
+ .macro clear_mte_async_tcf thread_sctlr
#ifdef CONFIG_ARM64_MTE
alternative_if ARM64_MTE
+ /* See comment in check_mte_async_tcf above. */
+ tbz \thread_sctlr, #(SCTLR_EL1_TCF0_SHIFT + 1), 1f
dsb ish
msr_s SYS_TFSRE0_EL1, xzr
+1:
alternative_else_nop_endif
#endif
.endm
- .macro mte_set_gcr, tmp, tmp2
+ .macro mte_set_gcr, mte_ctrl, tmp
#ifdef CONFIG_ARM64_MTE
- /*
- * Calculate and set the exclude mask preserving
- * the RRND (bit[16]) setting.
- */
- mrs_s \tmp2, SYS_GCR_EL1
- bfi \tmp2, \tmp, #0, #16
- msr_s SYS_GCR_EL1, \tmp2
+ ubfx \tmp, \mte_ctrl, #MTE_CTRL_GCR_USER_EXCL_SHIFT, #16
+ orr \tmp, \tmp, #SYS_GCR_EL1_RRND
+ msr_s SYS_GCR_EL1, \tmp
#endif
.endm
alternative_if_not ARM64_MTE
b 1f
alternative_else_nop_endif
- ldr_l \tmp, gcr_kernel_excl
-
- mte_set_gcr \tmp, \tmp2
- isb
+ mov \tmp, KERNEL_GCR_EL1
+ msr_s SYS_GCR_EL1, \tmp
1:
#endif
.endm
alternative_if_not ARM64_MTE
b 1f
alternative_else_nop_endif
- ldr \tmp, [\tsk, #THREAD_GCR_EL1_USER]
+ ldr \tmp, [\tsk, #THREAD_MTE_CTRL]
mte_set_gcr \tmp, \tmp2
1:
disable_step_tsk x19, x20
/* Check for asynchronous tag check faults in user space */
- check_mte_async_tcf x22, x23
- apply_ssbd 1, x22, x23
+ ldr x0, [tsk, THREAD_SCTLR_USER]
+ check_mte_async_tcf x22, x23, x0
#ifdef CONFIG_ARM64_PTR_AUTH
alternative_if ARM64_HAS_ADDRESS_AUTH
* was disabled on kernel exit then we would have left the kernel IA
* installed so there is no need to install it again.
*/
- ldr x0, [tsk, THREAD_SCTLR_USER]
tbz x0, SCTLR_ELx_ENIA_SHIFT, 1f
__ptrauth_keys_install_kernel_nosync tsk, x20, x22, x23
b 2f
orr x0, x0, SCTLR_ELx_ENIA
msr sctlr_el1, x0
2:
- isb
alternative_else_nop_endif
#endif
+ apply_ssbd 1, x22, x23
+
mte_set_kernel_gcr x22, x23
+ /*
+ * Any non-self-synchronizing system register updates required for
+ * kernel entry should be placed before this point.
+ */
+alternative_if ARM64_MTE
+ isb
+ b 1f
+alternative_else_nop_endif
+alternative_if ARM64_HAS_ADDRESS_AUTH
+ isb
+alternative_else_nop_endif
+1:
+
scs_load tsk
.else
add x21, sp, #PT_REGS_SIZE
3:
scs_save tsk
+ /* Ignore asynchronous tag check faults in the uaccess routines */
+ ldr x0, [tsk, THREAD_SCTLR_USER]
+ clear_mte_async_tcf x0
+
#ifdef CONFIG_ARM64_PTR_AUTH
alternative_if ARM64_HAS_ADDRESS_AUTH
/*
*
* No kernel C function calls after this.
*/
- ldr x0, [tsk, THREAD_SCTLR_USER]
tbz x0, SCTLR_ELx_ENIA_SHIFT, 1f
__ptrauth_keys_install_user tsk, x0, x1, x2
b 2f
/* GPRs used by entry code */
tsk .req x28 // current thread_info
-/*
- * Interrupt handling.
- */
- .macro gic_prio_kentry_setup, tmp:req
-#ifdef CONFIG_ARM64_PSEUDO_NMI
- alternative_if ARM64_HAS_IRQ_PRIO_MASKING
- mov \tmp, #(GIC_PRIO_PSR_I_SET | GIC_PRIO_IRQON)
- msr_s SYS_ICC_PMR_EL1, \tmp
- alternative_else_nop_endif
-#endif
- .endm
-
.text
/*
SYM_CODE_END(vectors)
#ifdef CONFIG_VMAP_STACK
+SYM_CODE_START_LOCAL(__bad_stack)
/*
* We detected an overflow in kernel_ventry, which switched to the
* overflow stack. Stash the exception regs, and head to our overflow
* handler.
*/
-__bad_stack:
+
/* Restore the original x0 value */
mrs x0, tpidrro_el0
/* Time to die */
bl handle_bad_stack
ASM_BUG()
+SYM_CODE_END(__bad_stack)
#endif /* CONFIG_VMAP_STACK */
kernel_exit 1
SYM_CODE_END(ret_to_kernel)
-/*
- * "slow" syscall return path.
- */
SYM_CODE_START_LOCAL(ret_to_user)
- disable_daif
- gic_prio_kentry_setup tmp=x3
-#ifdef CONFIG_TRACE_IRQFLAGS
- bl trace_hardirqs_off
-#endif
- ldr x19, [tsk, #TSK_TI_FLAGS]
- and x2, x19, #_TIF_WORK_MASK
- cbnz x2, work_pending
-finish_ret_to_user:
- user_enter_irqoff
- /* Ignore asynchronous tag check faults in the uaccess routines */
- clear_mte_async_tcf
+ ldr x19, [tsk, #TSK_TI_FLAGS] // re-check for single-step
enable_step_tsk x19, x2
#ifdef CONFIG_GCC_PLUGIN_STACKLEAK
bl stackleak_erase
#endif
kernel_exit 0
-
-/*
- * Ok, we need to do extra processing, enter the slow path.
- */
-work_pending:
- mov x0, sp // 'regs'
- mov x1, x19
- bl do_notify_resume
- ldr x19, [tsk, #TSK_TI_FLAGS] // re-check for single-step
- b finish_ret_to_user
SYM_CODE_END(ret_to_user)
.popsection // .entry.text
mov x0, x20
blr x19
1: get_current_task tsk
+ mov x0, sp
+ bl asm_exit_to_user_mode
b ret_to_user
SYM_CODE_END(ret_from_fork)
NOKPROBE(ret_from_fork)
projects / linux-2.6-microblaze.git / blobdiff