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arm64: entry: convert el0_sync to C

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This is largely a 1-1 conversion of asm to C, with a couple of caveats.

The el0_sync{_compat} switches explicitly handle all the EL0 debug
cases, so el0_dbg doesn't have to try to bail out for unexpected EL1
debug ESR values. This also means that an unexpected vector catch from
AArch32 is routed to el0_inv.

We *could* merge the native and compat switches, which would make the
diffstat negative, but I've tried to stay as close to the existing
assembly as possible for the moment.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[split out of a bigger series, added nokprobes. removed irq trace
 calls as the C helpers do this. renamed el0_dbg's use of FAR]
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Mark Rutland 2019-10-25 17:42:14 +01:00 committed by Catalin Marinas
parent ed3768db58
commit 582f95835a
3 changed files with 227 additions and 211 deletions
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10
arch/arm64/include/asm/asm-uaccess.h
View file

@ -74,14 +74,4 @@ alternative_if ARM64_ALT_PAN_NOT_UAO
SET_PSTATE_PAN(0)
alternative_else_nop_endif
.endm
/*
* Remove the address tag from a virtual address, if present.
*/
.macro clear_address_tag, dst, addr
tst \addr, #(1 << 55)
bic \dst, \addr, #(0xff << 56)
csel \dst, \dst, \addr, eq
.endm
#endif

222
arch/arm64/kernel/entry-common.c
View file

@ -96,3 +96,225 @@ asmlinkage void notrace el1_sync_handler(struct pt_regs *regs)
};
}
NOKPROBE_SYMBOL(el1_sync_handler);
static void notrace el0_da(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
far = untagged_addr(far);
do_mem_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el0_da);
static void notrace el0_ia(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX_NOIRQ);
do_el0_ia_bp_hardening(far, esr, regs);
}
NOKPROBE_SYMBOL(el0_ia);
static void notrace el0_fpsimd_acc(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_fpsimd_acc(esr, regs);
}
NOKPROBE_SYMBOL(el0_fpsimd_acc);
static void notrace el0_sve_acc(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_sve_acc(esr, regs);
}
NOKPROBE_SYMBOL(el0_sve_acc);
static void notrace el0_fpsimd_exc(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_fpsimd_exc(esr, regs);
}
NOKPROBE_SYMBOL(el0_fpsimd_exc);
static void notrace el0_sys(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_sysinstr(esr, regs);
}
NOKPROBE_SYMBOL(el0_sys);
static void notrace el0_pc(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX_NOIRQ);
do_sp_pc_abort(far, esr, regs);
}
NOKPROBE_SYMBOL(el0_pc);
static void notrace el0_sp(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX_NOIRQ);
do_sp_pc_abort(regs->sp, esr, regs);
}
NOKPROBE_SYMBOL(el0_sp);
static void notrace el0_undef(struct pt_regs *regs)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_undefinstr(regs);
}
NOKPROBE_SYMBOL(el0_undef);
static void notrace el0_inv(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
bad_el0_sync(regs, 0, esr);
}
NOKPROBE_SYMBOL(el0_inv);
static void notrace el0_dbg(struct pt_regs *regs, unsigned long esr)
{
/* Only watchpoints write FAR_EL1, otherwise its UNKNOWN */
unsigned long far = read_sysreg(far_el1);
if (system_uses_irq_prio_masking())
gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
user_exit_irqoff();
do_debug_exception(far, esr, regs);
local_daif_restore(DAIF_PROCCTX_NOIRQ);
}
NOKPROBE_SYMBOL(el0_dbg);
static void notrace el0_svc(struct pt_regs *regs)
{
if (system_uses_irq_prio_masking())
gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
el0_svc_handler(regs);
}
NOKPROBE_SYMBOL(el0_svc);
asmlinkage void notrace el0_sync_handler(struct pt_regs *regs)
{
unsigned long esr = read_sysreg(esr_el1);
switch (ESR_ELx_EC(esr)) {
case ESR_ELx_EC_SVC64:
el0_svc(regs);
break;
case ESR_ELx_EC_DABT_LOW:
el0_da(regs, esr);
break;
case ESR_ELx_EC_IABT_LOW:
el0_ia(regs, esr);
break;
case ESR_ELx_EC_FP_ASIMD:
el0_fpsimd_acc(regs, esr);
break;
case ESR_ELx_EC_SVE:
el0_sve_acc(regs, esr);
break;
case ESR_ELx_EC_FP_EXC64:
el0_fpsimd_exc(regs, esr);
break;
case ESR_ELx_EC_SYS64:
case ESR_ELx_EC_WFx:
el0_sys(regs, esr);
break;
case ESR_ELx_EC_SP_ALIGN:
el0_sp(regs, esr);
break;
case ESR_ELx_EC_PC_ALIGN:
el0_pc(regs, esr);
break;
case ESR_ELx_EC_UNKNOWN:
el0_undef(regs);
break;
case ESR_ELx_EC_BREAKPT_LOW:
case ESR_ELx_EC_SOFTSTP_LOW:
case ESR_ELx_EC_WATCHPT_LOW:
case ESR_ELx_EC_BRK64:
el0_dbg(regs, esr);
break;
default:
el0_inv(regs, esr);
}
}
NOKPROBE_SYMBOL(el0_sync_handler);
#ifdef CONFIG_COMPAT
static void notrace el0_cp15(struct pt_regs *regs, unsigned long esr)
{
user_exit_irqoff();
local_daif_restore(DAIF_PROCCTX);
do_cp15instr(esr, regs);
}
NOKPROBE_SYMBOL(el0_cp15);
static void notrace el0_svc_compat(struct pt_regs *regs)
{
if (system_uses_irq_prio_masking())
gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
el0_svc_compat_handler(regs);
}
NOKPROBE_SYMBOL(el0_svc_compat);
asmlinkage void notrace el0_sync_compat_handler(struct pt_regs *regs)
{
unsigned long esr = read_sysreg(esr_el1);
switch (ESR_ELx_EC(esr)) {
case ESR_ELx_EC_SVC32:
el0_svc_compat(regs);
break;
case ESR_ELx_EC_DABT_LOW:
el0_da(regs, esr);
break;
case ESR_ELx_EC_IABT_LOW:
el0_ia(regs, esr);
break;
case ESR_ELx_EC_FP_ASIMD:
el0_fpsimd_acc(regs, esr);
break;
case ESR_ELx_EC_FP_EXC32:
el0_fpsimd_exc(regs, esr);
break;
case ESR_ELx_EC_PC_ALIGN:
el0_pc(regs, esr);
break;
case ESR_ELx_EC_UNKNOWN:
case ESR_ELx_EC_CP14_MR:
case ESR_ELx_EC_CP14_LS:
case ESR_ELx_EC_CP14_64:
el0_undef(regs);
break;
case ESR_ELx_EC_CP15_32:
case ESR_ELx_EC_CP15_64:
el0_cp15(regs, esr);
break;
case ESR_ELx_EC_BREAKPT_LOW:
case ESR_ELx_EC_SOFTSTP_LOW:
case ESR_ELx_EC_WATCHPT_LOW:
case ESR_ELx_EC_BKPT32:
el0_dbg(regs, esr);
break;
default:
el0_inv(regs, esr);
}
}
NOKPROBE_SYMBOL(el0_sync_compat_handler);
#endif /* CONFIG_COMPAT */

206
arch/arm64/kernel/entry.S
View file

@ -647,71 +647,18 @@ ENDPROC(el1_irq)
.align 6
el0_sync:
kernel_entry 0
mrs x25, esr_el1 // read the syndrome register
lsr x24, x25, #ESR_ELx_EC_SHIFT // exception class
cmp x24, #ESR_ELx_EC_SVC64 // SVC in 64-bit state
b.eq el0_svc
cmp x24, #ESR_ELx_EC_DABT_LOW // data abort in EL0
b.eq el0_da
cmp x24, #ESR_ELx_EC_IABT_LOW // instruction abort in EL0
b.eq el0_ia
cmp x24, #ESR_ELx_EC_FP_ASIMD // FP/ASIMD access
b.eq el0_fpsimd_acc
cmp x24, #ESR_ELx_EC_SVE // SVE access
b.eq el0_sve_acc
cmp x24, #ESR_ELx_EC_FP_EXC64 // FP/ASIMD exception
b.eq el0_fpsimd_exc
cmp x24, #ESR_ELx_EC_SYS64 // configurable trap
ccmp x24, #ESR_ELx_EC_WFx, #4, ne
b.eq el0_sys
cmp x24, #ESR_ELx_EC_SP_ALIGN // stack alignment exception
b.eq el0_sp
cmp x24, #ESR_ELx_EC_PC_ALIGN // pc alignment exception
b.eq el0_pc
cmp x24, #ESR_ELx_EC_UNKNOWN // unknown exception in EL0
b.eq el0_undef
cmp x24, #ESR_ELx_EC_BREAKPT_LOW // debug exception in EL0
b.ge el0_dbg
b el0_inv
mov x0, sp
bl el0_sync_handler
b ret_to_user
#ifdef CONFIG_COMPAT
.align 6
el0_sync_compat:
kernel_entry 0, 32
mrs x25, esr_el1 // read the syndrome register
lsr x24, x25, #ESR_ELx_EC_SHIFT // exception class
cmp x24, #ESR_ELx_EC_SVC32 // SVC in 32-bit state
b.eq el0_svc_compat
cmp x24, #ESR_ELx_EC_DABT_LOW // data abort in EL0
b.eq el0_da
cmp x24, #ESR_ELx_EC_IABT_LOW // instruction abort in EL0
b.eq el0_ia
cmp x24, #ESR_ELx_EC_FP_ASIMD // FP/ASIMD access
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_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
b.eq el0_cp15
cmp x24, #ESR_ELx_EC_CP15_64 // CP15 MRRC/MCRR trap
b.eq el0_cp15
cmp x24, #ESR_ELx_EC_CP14_MR // CP14 MRC/MCR trap
b.eq el0_undef
cmp x24, #ESR_ELx_EC_CP14_LS // CP14 LDC/STC trap
b.eq el0_undef
cmp x24, #ESR_ELx_EC_CP14_64 // CP14 MRRC/MCRR trap
b.eq el0_undef
cmp x24, #ESR_ELx_EC_BREAKPT_LOW // debug exception in EL0
b.ge el0_dbg
b el0_inv
el0_svc_compat:
gic_prio_kentry_setup tmp=x1
mov x0, sp
bl el0_svc_compat_handler
bl el0_sync_compat_handler
b ret_to_user
ENDPROC(el0_sync)
.align 6
el0_irq_compat:
@ -721,140 +668,8 @@ el0_irq_compat:
el0_error_compat:
kernel_entry 0, 32
b el0_error_naked
el0_cp15:
/*
* Trapped CP15 (MRC, MCR, MRRC, MCRR) instructions
*/
ct_user_exit_irqoff
enable_daif
mov x0, x25
mov x1, sp
bl do_cp15instr
b ret_to_user
#endif
el0_da:
/*
* Data abort handling
*/
mrs x26, far_el1
ct_user_exit_irqoff
enable_daif
clear_address_tag x0, x26
mov x1, x25
mov x2, sp
bl do_mem_abort
b ret_to_user
el0_ia:
/*
* Instruction abort handling
*/
mrs x26, far_el1
gic_prio_kentry_setup tmp=x0
ct_user_exit_irqoff
enable_da_f
#ifdef CONFIG_TRACE_IRQFLAGS
bl trace_hardirqs_off
#endif
mov x0, x26
mov x1, x25
mov x2, sp
bl do_el0_ia_bp_hardening
b ret_to_user
el0_fpsimd_acc:
/*
* Floating Point or Advanced SIMD access
*/
ct_user_exit_irqoff
enable_daif
mov x0, x25
mov x1, sp
bl do_fpsimd_acc
b ret_to_user
el0_sve_acc:
/*
* Scalable Vector Extension access
*/
ct_user_exit_irqoff
enable_daif
mov x0, x25
mov x1, sp
bl do_sve_acc
b ret_to_user
el0_fpsimd_exc:
/*
* Floating Point, Advanced SIMD or SVE exception
*/
ct_user_exit_irqoff
enable_daif
mov x0, x25
mov x1, sp
bl do_fpsimd_exc
b ret_to_user
el0_sp:
ldr x26, [sp, #S_SP]
b el0_sp_pc
el0_pc:
mrs x26, far_el1
el0_sp_pc:
/*
* Stack or PC alignment exception handling
*/
gic_prio_kentry_setup tmp=x0
ct_user_exit_irqoff
enable_da_f
#ifdef CONFIG_TRACE_IRQFLAGS
bl trace_hardirqs_off
#endif
mov x0, x26
mov x1, x25
mov x2, sp
bl do_sp_pc_abort
b ret_to_user
el0_undef:
/*
* Undefined instruction
*/
ct_user_exit_irqoff
enable_daif
mov x0, sp
bl do_undefinstr
b ret_to_user
el0_sys:
/*
* System instructions, for trapped cache maintenance instructions
*/
ct_user_exit_irqoff
enable_daif
mov x0, x25
mov x1, sp
bl do_sysinstr
b ret_to_user
el0_dbg:
/*
* Debug exception handling
*/
tbnz x24, #0, el0_inv // EL0 only
mrs x24, far_el1
gic_prio_kentry_setup tmp=x3
ct_user_exit_irqoff
mov x0, x24
mov x1, x25
mov x2, sp
bl do_debug_exception
enable_da_f
b ret_to_user
el0_inv:
ct_user_exit_irqoff
enable_daif
mov x0, sp
mov x1, #BAD_SYNC
mov x2, x25
bl bad_el0_sync
b ret_to_user
ENDPROC(el0_sync)
.align 6
el0_irq:
kernel_entry 0
@ -932,17 +747,6 @@ finish_ret_to_user:
kernel_exit 0
ENDPROC(ret_to_user)
/*
* SVC handler.
*/
.align 6
el0_svc:
gic_prio_kentry_setup tmp=x1
mov x0, sp
bl el0_svc_handler
b ret_to_user
ENDPROC(el0_svc)
.popsection // .entry.text
#ifdef CONFIG_UNMAP_KERNEL_AT_EL0