syscall
=======
+Invocation
+----------
+The syscall is made with the sc instruction, and returns with execution
+continuing at the instruction following the sc instruction.
+
+If PPC_FEATURE2_SCV appears in the AT_HWCAP2 ELF auxiliary vector, the
+scv 0 instruction is an alternative that may provide better performance,
+with some differences to calling sequence.
+
syscall calling sequence\ [1]_ matches the Power Architecture 64-bit ELF ABI
specification C function calling sequence, including register preservation
rules, with the following differences.
.. [1] Some syscalls (typically low-level management functions) may have
different calling sequences (e.g., rt_sigreturn).
-Parameters and return value
----------------------------
+Parameters
+----------
The system call number is specified in r0.
There is a maximum of 6 integer parameters to a syscall, passed in r3-r8.
-Both a return value and a return error code are returned. cr0.SO is the return
-error code, and r3 is the return value or error code. When cr0.SO is clear,
-the syscall succeeded and r3 is the return value. When cr0.SO is set, the
-syscall failed and r3 is the error code that generally corresponds to errno.
+Return value
+------------
+- For the sc instruction, both a value and an error condition are returned.
+ cr0.SO is the error condition, and r3 is the return value. When cr0.SO is
+ clear, the syscall succeeded and r3 is the return value. When cr0.SO is set,
+ the syscall failed and r3 is the error value (that normally corresponds to
+ errno).
+
+- For the scv 0 instruction, the return value indicates failure if it is
+ -4095..-1 (i.e., it is >= -MAX_ERRNO (-4095) as an unsigned comparison),
+ in which case the error value is the negated return value.
Stack
-----
following differences:
=========== ============= ========================================
+--- For the sc instruction, differences with the ELF ABI ---
r0 Volatile (System call number.)
r3 Volatile (Parameter 1, and return value.)
r4-r8 Volatile (Parameters 2-6.)
-cr0 Volatile (cr0.SO is the return error condition)
+cr0 Volatile (cr0.SO is the return error condition.)
cr1, cr5-7 Nonvolatile
lr Nonvolatile
+
+--- For the scv 0 instruction, differences with the ELF ABI ---
+r0 Volatile (System call number.)
+r3 Volatile (Parameter 1, and return value.)
+r4-r8 Volatile (Parameters 2-6.)
=========== ============= ========================================
All floating point and vector data registers as well as control and status
registers are nonvolatile.
-Invocation
-----------
-The syscall is performed with the sc instruction, and returns with execution
-continuing at the instruction following the sc instruction.
-
Transactional Memory
--------------------
Syscall behavior can change if the processor is in transactional or suspended
returning to the caller. This case is not well defined or supported, so this
behavior should not be relied upon.
+scv 0 syscalls will always behave as PPC_FEATURE2_HTM_NOSC.
vsyscall
========
void __init machine_init(u64 dt_ptr);
#endif
long system_call_exception(long r3, long r4, long r5, long r6, long r7, long r8, unsigned long r0, struct pt_regs *regs);
-notrace unsigned long syscall_exit_prepare(unsigned long r3, struct pt_regs *regs);
+notrace unsigned long syscall_exit_prepare(unsigned long r3, struct pt_regs *regs, long scv);
notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs, unsigned long msr);
notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs, unsigned long msr);
hrfid; \
b hrfi_flush_fallback
+#define RFSCV_TO_USER \
+ STF_EXIT_BARRIER_SLOT; \
+ RFI_FLUSH_SLOT; \
+ RFSCV; \
+ b rfscv_flush_fallback
+
#endif /* __ASSEMBLY__ */
#endif /* _ASM_POWERPC_EXCEPTION_H */
.if ((start) % (size) != 0); \
.error "Fixed section exception vector misalignment"; \
.endif; \
- .if ((size) != 0x20) && ((size) != 0x80) && ((size) != 0x100); \
+ .if ((size) != 0x20) && ((size) != 0x80) && ((size) != 0x100) && ((size) != 0x1000); \
.error "Fixed section exception vector bad size"; \
.endif; \
.if (start) < sname##_start; \
#define N_SLINE 68
#define N_SO 100
+#define RFSCV .long 0x4c0000a4
+
/*
* Create an endian fixup trampoline
*
regs->trap = (regs->trap & TRAP_FLAGS_MASK) | (val & ~TRAP_FLAGS_MASK);
}
+static inline bool trap_is_scv(struct pt_regs *regs)
+{
+ return (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && TRAP(regs) == 0x3000);
+}
+
static inline bool trap_is_syscall(struct pt_regs *regs)
{
- return TRAP(regs) == 0xc00;
+ return (trap_is_scv(regs) || TRAP(regs) == 0xc00);
}
static inline bool trap_norestart(struct pt_regs *regs)
#define ARCH_PANIC_TIMEOUT 180
#ifdef CONFIG_PPC_PSERIES
-extern void pseries_enable_reloc_on_exc(void);
+extern bool pseries_enable_reloc_on_exc(void);
extern void pseries_disable_reloc_on_exc(void);
extern void pseries_big_endian_exceptions(void);
extern void pseries_little_endian_exceptions(void);
#else
-static inline void pseries_enable_reloc_on_exc(void) {}
+static inline bool pseries_enable_reloc_on_exc(void) { return false; }
static inline void pseries_disable_reloc_on_exc(void) {}
static inline void pseries_big_endian_exceptions(void) {}
static inline void pseries_little_endian_exceptions(void) {}
CACHEOP,
BARRIER,
SYSCALL,
+ SYSCALL_VECTORED_0,
MFMSR,
MTMSR,
RFI,
_GLOBAL(__setup_cpu_power9)
mflr r11
- bl __init_FSCR
+ bl __init_FSCR_power9
1: bl __init_PMU
bl __init_hvmode_206
mtlr r11
_GLOBAL(__restore_cpu_power9)
mflr r11
- bl __init_FSCR
+ bl __init_FSCR_power9
1: bl __init_PMU
mfmsr r3
rldicl. r0,r3,4,63
mtspr SPRN_FSCR, r3
// fall through
+__init_FSCR_power9:
+ mfspr r3, SPRN_FSCR
+ ori r3, r3, FSCR_SCV
+ mtspr SPRN_FSCR, r3
+ // fall through
+
__init_FSCR:
mfspr r3,SPRN_FSCR
ori r3,r3,FSCR_TAR|FSCR_EBB
#define COMMON_USER2_POWER9 (COMMON_USER2_POWER8 | \
PPC_FEATURE2_ARCH_3_00 | \
PPC_FEATURE2_HAS_IEEE128 | \
- PPC_FEATURE2_DARN )
+ PPC_FEATURE2_DARN | \
+ PPC_FEATURE2_SCV)
#define COMMON_USER_POWER10 COMMON_USER_POWER9
#define COMMON_USER2_POWER10 (COMMON_USER2_POWER9 | \
PPC_FEATURE2_ARCH_3_1 | \
{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
{"smt", feat_enable_smt, 0},
{"interrupt-facilities", feat_enable, 0},
+ {"system-call-vectored", feat_enable, 0},
{"timer-facilities", feat_enable, 0},
{"timer-facilities-v3", feat_enable, 0},
{"debug-facilities", feat_enable, 0},
.section ".text"
.align 7
+#ifdef CONFIG_PPC_BOOK3S
+.macro system_call_vectored name trapnr
+ .globl system_call_vectored_\name
+system_call_vectored_\name:
+_ASM_NOKPROBE_SYMBOL(system_call_vectored_\name)
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+BEGIN_FTR_SECTION
+ extrdi. r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */
+ bne .Ltabort_syscall
+END_FTR_SECTION_IFSET(CPU_FTR_TM)
+#endif
+ INTERRUPT_TO_KERNEL
+ mr r10,r1
+ ld r1,PACAKSAVE(r13)
+ std r10,0(r1)
+ std r11,_NIP(r1)
+ std r12,_MSR(r1)
+ std r0,GPR0(r1)
+ std r10,GPR1(r1)
+ std r2,GPR2(r1)
+ ld r2,PACATOC(r13)
+ mfcr r12
+ li r11,0
+ /* Can we avoid saving r3-r8 in common case? */
+ std r3,GPR3(r1)
+ std r4,GPR4(r1)
+ std r5,GPR5(r1)
+ std r6,GPR6(r1)
+ std r7,GPR7(r1)
+ std r8,GPR8(r1)
+ /* Zero r9-r12, this should only be required when restoring all GPRs */
+ std r11,GPR9(r1)
+ std r11,GPR10(r1)
+ std r11,GPR11(r1)
+ std r11,GPR12(r1)
+ std r9,GPR13(r1)
+ SAVE_NVGPRS(r1)
+ std r11,_XER(r1)
+ std r11,_LINK(r1)
+ std r11,_CTR(r1)
+
+ li r11,\trapnr
+ std r11,_TRAP(r1)
+ std r12,_CCR(r1)
+ std r3,ORIG_GPR3(r1)
+ addi r10,r1,STACK_FRAME_OVERHEAD
+ ld r11,exception_marker@toc(r2)
+ std r11,-16(r10) /* "regshere" marker */
+
+ /*
+ * RECONCILE_IRQ_STATE without calling trace_hardirqs_off(), which
+ * would clobber syscall parameters. Also we always enter with IRQs
+ * enabled and nothing pending. system_call_exception() will call
+ * trace_hardirqs_off().
+ *
+ * scv enters with MSR[EE]=1, so don't set PACA_IRQ_HARD_DIS. The
+ * entry vector already sets PACAIRQSOFTMASK to IRQS_ALL_DISABLED.
+ */
+
+ /* Calling convention has r9 = orig r0, r10 = regs */
+ mr r9,r0
+ bl system_call_exception
+
+.Lsyscall_vectored_\name\()_exit:
+ addi r4,r1,STACK_FRAME_OVERHEAD
+ li r5,1 /* scv */
+ bl syscall_exit_prepare
+
+ ld r2,_CCR(r1)
+ ld r4,_NIP(r1)
+ ld r5,_MSR(r1)
+
+BEGIN_FTR_SECTION
+ stdcx. r0,0,r1 /* to clear the reservation */
+END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
+
+BEGIN_FTR_SECTION
+ HMT_MEDIUM_LOW
+END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
+
+ cmpdi r3,0
+ bne .Lsyscall_vectored_\name\()_restore_regs
+
+ /* rfscv returns with LR->NIA and CTR->MSR */
+ mtlr r4
+ mtctr r5
+
+ /* Could zero these as per ABI, but we may consider a stricter ABI
+ * which preserves these if libc implementations can benefit, so
+ * restore them for now until further measurement is done. */
+ ld r0,GPR0(r1)
+ ld r4,GPR4(r1)
+ ld r5,GPR5(r1)
+ ld r6,GPR6(r1)
+ ld r7,GPR7(r1)
+ ld r8,GPR8(r1)
+ /* Zero volatile regs that may contain sensitive kernel data */
+ li r9,0
+ li r10,0
+ li r11,0
+ li r12,0
+ mtspr SPRN_XER,r0
+
+ /*
+ * We don't need to restore AMR on the way back to userspace for KUAP.
+ * The value of AMR only matters while we're in the kernel.
+ */
+ mtcr r2
+ ld r2,GPR2(r1)
+ ld r3,GPR3(r1)
+ ld r13,GPR13(r1)
+ ld r1,GPR1(r1)
+ RFSCV_TO_USER
+ b . /* prevent speculative execution */
+
+.Lsyscall_vectored_\name\()_restore_regs:
+ li r3,0
+ mtmsrd r3,1
+ mtspr SPRN_SRR0,r4
+ mtspr SPRN_SRR1,r5
+
+ ld r3,_CTR(r1)
+ ld r4,_LINK(r1)
+ ld r5,_XER(r1)
+
+ REST_NVGPRS(r1)
+ ld r0,GPR0(r1)
+ mtcr r2
+ mtctr r3
+ mtlr r4
+ mtspr SPRN_XER,r5
+ REST_10GPRS(2, r1)
+ REST_2GPRS(12, r1)
+ ld r1,GPR1(r1)
+ RFI_TO_USER
+.endm
+
+system_call_vectored common 0x3000
+/*
+ * We instantiate another entry copy for the SIGILL variant, with TRAP=0x7ff0
+ * which is tested by system_call_exception when r0 is -1 (as set by vector
+ * entry code).
+ */
+system_call_vectored sigill 0x7ff0
+
+
+/*
+ * Entered via kernel return set up by kernel/sstep.c, must match entry regs
+ */
+ .globl system_call_vectored_emulate
+system_call_vectored_emulate:
+_ASM_NOKPROBE_SYMBOL(system_call_vectored_emulate)
+ li r10,IRQS_ALL_DISABLED
+ stb r10,PACAIRQSOFTMASK(r13)
+ b system_call_vectored_common
+#endif
+
+ .balign IFETCH_ALIGN_BYTES
.globl system_call_common
system_call_common:
+_ASM_NOKPROBE_SYMBOL(system_call_common)
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
BEGIN_FTR_SECTION
extrdi. r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */
bne .Ltabort_syscall
END_FTR_SECTION_IFSET(CPU_FTR_TM)
#endif
-_ASM_NOKPROBE_SYMBOL(system_call_common)
mr r10,r1
ld r1,PACAKSAVE(r13)
std r10,0(r1)
.Lsyscall_exit:
addi r4,r1,STACK_FRAME_OVERHEAD
+ li r5,0 /* !scv */
bl syscall_exit_prepare
ld r2,_CCR(r1)
b . /* prevent speculative execution */
#endif
+#ifdef CONFIG_PPC_BOOK3S
+_GLOBAL(ret_from_fork_scv)
+ bl schedule_tail
+ REST_NVGPRS(r1)
+ li r3,0 /* fork() return value */
+ b .Lsyscall_vectored_common_exit
+#endif
+
_GLOBAL(ret_from_fork)
bl schedule_tail
REST_NVGPRS(r1)
- li r3,0
+ li r3,0 /* fork() return value */
b .Lsyscall_exit
_GLOBAL(ret_from_kernel_thread)
* guarantee they will be delivered virtually. Some conditions (see the ISA)
* cause exceptions to be delivered in real mode.
*
+ * The scv instructions are a special case. They get a 0x3000 offset applied.
+ * scv exceptions have unique reentrancy properties, see below.
+ *
* It's impossible to receive interrupts below 0x300 via AIL.
*
* KVM: None of the virtual exceptions are from the guest. Anything that
* We layout physical memory as follows:
* 0x0000 - 0x00ff : Secondary processor spin code
* 0x0100 - 0x18ff : Real mode pSeries interrupt vectors
- * 0x1900 - 0x3fff : Real mode trampolines
- * 0x4000 - 0x58ff : Relon (IR=1,DR=1) mode pSeries interrupt vectors
+ * 0x1900 - 0x2fff : Real mode trampolines
+ * 0x3000 - 0x58ff : Relon (IR=1,DR=1) mode pSeries interrupt vectors
* 0x5900 - 0x6fff : Relon mode trampolines
* 0x7000 - 0x7fff : FWNMI data area
* 0x8000 - .... : Common interrupt handlers, remaining early
* vectors there.
*/
OPEN_FIXED_SECTION(real_vectors, 0x0100, 0x1900)
-OPEN_FIXED_SECTION(real_trampolines, 0x1900, 0x4000)
-OPEN_FIXED_SECTION(virt_vectors, 0x4000, 0x5900)
+OPEN_FIXED_SECTION(real_trampolines, 0x1900, 0x3000)
+OPEN_FIXED_SECTION(virt_vectors, 0x3000, 0x5900)
OPEN_FIXED_SECTION(virt_trampolines, 0x5900, 0x7000)
#ifdef CONFIG_PPC_POWERNV
.globl __start_interrupts
__start_interrupts:
+/**
+ * Interrupt 0x3000 - System Call Vectored Interrupt (syscall).
+ * This is a synchronous interrupt invoked with the "scv" instruction. The
+ * system call does not alter the HV bit, so it is directed to the OS.
+ *
+ * Handling:
+ * scv instructions enter the kernel without changing EE, RI, ME, or HV.
+ * In particular, this means we can take a maskable interrupt at any point
+ * in the scv handler, which is unlike any other interrupt. This is solved
+ * by treating the instruction addresses below __end_interrupts as being
+ * soft-masked.
+ *
+ * AIL-0 mode scv exceptions go to 0x17000-0x17fff, but we set AIL-3 and
+ * ensure scv is never executed with relocation off, which means AIL-0
+ * should never happen.
+ *
+ * Before leaving the below __end_interrupts text, at least of the following
+ * must be true:
+ * - MSR[PR]=1 (i.e., return to userspace)
+ * - MSR_EE|MSR_RI is set (no reentrant exceptions)
+ * - Standard kernel environment is set up (stack, paca, etc)
+ *
+ * Call convention:
+ *
+ * syscall register convention is in Documentation/powerpc/syscall64-abi.rst
+ */
+EXC_VIRT_BEGIN(system_call_vectored, 0x3000, 0x1000)
+ /* SCV 0 */
+ mr r9,r13
+ GET_PACA(r13)
+ mflr r11
+ mfctr r12
+ li r10,IRQS_ALL_DISABLED
+ stb r10,PACAIRQSOFTMASK(r13)
+#ifdef CONFIG_RELOCATABLE
+ b system_call_vectored_tramp
+#else
+ b system_call_vectored_common
+#endif
+ nop
+
+ /* SCV 1 - 127 */
+ .rept 127
+ mr r9,r13
+ GET_PACA(r13)
+ mflr r11
+ mfctr r12
+ li r10,IRQS_ALL_DISABLED
+ stb r10,PACAIRQSOFTMASK(r13)
+ li r0,-1 /* cause failure */
+#ifdef CONFIG_RELOCATABLE
+ b system_call_vectored_sigill_tramp
+#else
+ b system_call_vectored_sigill
+#endif
+ .endr
+EXC_VIRT_END(system_call_vectored, 0x3000, 0x1000)
+
+#ifdef CONFIG_RELOCATABLE
+TRAMP_VIRT_BEGIN(system_call_vectored_tramp)
+ __LOAD_HANDLER(r10, system_call_vectored_common)
+ mtctr r10
+ bctr
+
+TRAMP_VIRT_BEGIN(system_call_vectored_sigill_tramp)
+ __LOAD_HANDLER(r10, system_call_vectored_sigill)
+ mtctr r10
+ bctr
+#endif
+
+
/* No virt vectors corresponding with 0x0..0x100 */
EXC_VIRT_NONE(0x4000, 0x100)
GET_SCRATCH0(r13);
hrfid
+TRAMP_REAL_BEGIN(rfscv_flush_fallback)
+ /* system call volatile */
+ mr r7,r13
+ GET_PACA(r13);
+ mr r8,r1
+ ld r1,PACAKSAVE(r13)
+ mfctr r9
+ ld r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13)
+ ld r11,PACA_L1D_FLUSH_SIZE(r13)
+ srdi r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */
+ mtctr r11
+ DCBT_BOOK3S_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */
+
+ /* order ld/st prior to dcbt stop all streams with flushing */
+ sync
+
+ /*
+ * The load adresses are at staggered offsets within cachelines,
+ * which suits some pipelines better (on others it should not
+ * hurt).
+ */
+1:
+ ld r11,(0x80 + 8)*0(r10)
+ ld r11,(0x80 + 8)*1(r10)
+ ld r11,(0x80 + 8)*2(r10)
+ ld r11,(0x80 + 8)*3(r10)
+ ld r11,(0x80 + 8)*4(r10)
+ ld r11,(0x80 + 8)*5(r10)
+ ld r11,(0x80 + 8)*6(r10)
+ ld r11,(0x80 + 8)*7(r10)
+ addi r10,r10,0x80*8
+ bdnz 1b
+
+ mtctr r9
+ li r9,0
+ li r10,0
+ li r11,0
+ mr r1,r8
+ mr r13,r7
+ RFSCV
+
USE_TEXT_SECTION()
MASKED_INTERRUPT
MASKED_INTERRUPT hsrr=1
{
struct pt_regs *childregs, *kregs;
extern void ret_from_fork(void);
+ extern void ret_from_fork_scv(void);
extern void ret_from_kernel_thread(void);
void (*f)(void);
unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
if (usp)
childregs->gpr[1] = usp;
p->thread.regs = childregs;
- childregs->gpr[3] = 0; /* Result from fork() */
+ /* 64s sets this in ret_from_fork */
+ if (!IS_ENABLED(CONFIG_PPC_BOOK3S_64))
+ childregs->gpr[3] = 0; /* Result from fork() */
if (clone_flags & CLONE_SETTLS) {
if (!is_32bit_task())
childregs->gpr[13] = tls;
childregs->gpr[2] = tls;
}
- f = ret_from_fork;
+ if (trap_is_scv(regs))
+ f = ret_from_fork_scv;
+ else
+ f = ret_from_fork;
}
childregs->msr &= ~(MSR_FP|MSR_VEC|MSR_VSX);
sp -= STACK_FRAME_OVERHEAD;
/* Under a PAPR hypervisor, we need hypercalls */
if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
/* Enable AIL if possible */
- pseries_enable_reloc_on_exc();
+ if (!pseries_enable_reloc_on_exc()) {
+ init_task.thread.fscr &= ~FSCR_SCV;
+ cur_cpu_spec->cpu_user_features2 &= ~PPC_FEATURE2_SCV;
+ }
/*
* Tell the hypervisor that we want our exceptions to
return;
/* error signalled ? */
- if (!(regs->ccr & 0x10000000))
+ if (trap_is_scv(regs)) {
+ /* 32-bit compat mode sign extend? */
+ if (!IS_ERR_VALUE(ret))
+ return;
+ ret = -ret;
+ } else if (!(regs->ccr & 0x10000000)) {
return;
+ }
switch (ret) {
case ERESTART_RESTARTBLOCK:
regs->nip -= 4;
regs->result = 0;
} else {
- regs->result = -EINTR;
- regs->gpr[3] = EINTR;
- regs->ccr |= 0x10000000;
+ if (trap_is_scv(regs)) {
+ regs->result = -EINTR;
+ regs->gpr[3] = -EINTR;
+ } else {
+ regs->result = -EINTR;
+ regs->gpr[3] = EINTR;
+ regs->ccr |= 0x10000000;
+ }
}
}
local_irq_enable();
if (unlikely(current_thread_info()->flags & _TIF_SYSCALL_DOTRACE)) {
+ if (unlikely(regs->trap == 0x7ff0)) {
+ /* Unsupported scv vector */
+ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
+ return regs->gpr[3];
+ }
/*
* We use the return value of do_syscall_trace_enter() as the
* syscall number. If the syscall was rejected for any reason
r8 = regs->gpr[8];
} else if (unlikely(r0 >= NR_syscalls)) {
+ if (unlikely(regs->trap == 0x7ff0)) {
+ /* Unsupported scv vector */
+ _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
+ return regs->gpr[3];
+ }
return -ENOSYS;
}
* local irqs must be disabled. Returns false if the caller must re-enable
* them, check for new work, and try again.
*/
-static notrace inline bool prep_irq_for_enabled_exit(void)
+static notrace inline bool prep_irq_for_enabled_exit(bool clear_ri)
{
/* This must be done with RI=1 because tracing may touch vmaps */
trace_hardirqs_on();
/* This pattern matches prep_irq_for_idle */
- __hard_EE_RI_disable();
+ if (clear_ri)
+ __hard_EE_RI_disable();
+ else
+ __hard_irq_disable();
if (unlikely(lazy_irq_pending_nocheck())) {
/* Took an interrupt, may have more exit work to do. */
- __hard_RI_enable();
+ if (clear_ri)
+ __hard_RI_enable();
trace_hardirqs_off();
local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
* because RI=0 and soft mask state is "unreconciled", so it is marked notrace.
*/
notrace unsigned long syscall_exit_prepare(unsigned long r3,
- struct pt_regs *regs)
+ struct pt_regs *regs,
+ long scv)
{
unsigned long *ti_flagsp = ¤t_thread_info()->flags;
unsigned long ti_flags;
ti_flags = *ti_flagsp;
- if (unlikely(r3 >= (unsigned long)-MAX_ERRNO)) {
+ if (unlikely(r3 >= (unsigned long)-MAX_ERRNO) && !scv) {
if (likely(!(ti_flags & (_TIF_NOERROR | _TIF_RESTOREALL)))) {
r3 = -r3;
regs->ccr |= 0x10000000; /* Set SO bit in CR */
}
}
- if (unlikely(!prep_irq_for_enabled_exit())) {
+ /* scv need not set RI=0 because SRRs are not used */
+ if (unlikely(!prep_irq_for_enabled_exit(!scv))) {
local_irq_enable();
goto again;
}
}
}
- if (unlikely(!prep_irq_for_enabled_exit())) {
+ if (unlikely(!prep_irq_for_enabled_exit(true))) {
local_irq_enable();
local_irq_disable();
goto again;
}
}
- if (unlikely(!prep_irq_for_enabled_exit())) {
+ if (unlikely(!prep_irq_for_enabled_exit(true))) {
/*
* Can't local_irq_restore to replay if we were in
* interrupt context. Must replay directly.
#include <asm/disassemble.h>
extern char system_call_common[];
+extern char system_call_vectored_emulate[];
#ifdef CONFIG_PPC64
/* Bits in SRR1 that are copied from MSR */
case 17: /* sc */
if ((word & 0xfe2) == 2)
op->type = SYSCALL;
+ else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) &&
+ (word & 0xfe3) == 1)
+ op->type = SYSCALL_VECTORED_0;
else
op->type = UNKNOWN;
return 0;
regs->msr = MSR_KERNEL;
return 1;
+#ifdef CONFIG_PPC64_BOOK3S
+ case SYSCALL_VECTORED_0: /* scv 0 */
+ regs->gpr[9] = regs->gpr[13];
+ regs->gpr[10] = MSR_KERNEL;
+ regs->gpr[11] = regs->nip + 4;
+ regs->gpr[12] = regs->msr & MSR_MASK;
+ regs->gpr[13] = (unsigned long) get_paca();
+ regs->nip = (unsigned long) &system_call_vectored_emulate;
+ regs->msr = MSR_KERNEL;
+ return 1;
+#endif
+
case RFI:
return -1;
#endif
* to ever be a problem in practice we can move this into a kernel thread to
* finish off the process later in boot.
*/
-void pseries_enable_reloc_on_exc(void)
+bool pseries_enable_reloc_on_exc(void)
{
long rc;
unsigned int delay, total_delay = 0;
if (rc == H_P2) {
pr_info("Relocation on exceptions not"
" supported\n");
+ return false;
} else if (rc != H_SUCCESS) {
pr_warn("Unable to enable relocation"
" on exceptions: %ld\n", rc);
+ return false;
}
- break;
+ return true;
}
delay = get_longbusy_msecs(rc);
pr_warn("Warning: Giving up waiting to enable "
"relocation on exceptions (%u msec)!\n",
total_delay);
- return;
+ return false;
}
mdelay(delay);
case 0x1300: ret = "(Instruction Breakpoint)"; break;
case 0x1500: ret = "(Denormalisation)"; break;
case 0x1700: ret = "(Altivec Assist)"; break;
+ case 0x3000: ret = "(System Call Vectored)"; break;
default: ret = "";
}
return ret;
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