summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--arch/s390/include/asm/ptrace.h5
-rw-r--r--arch/s390/include/asm/syscall.h5
-rw-r--r--arch/s390/include/asm/thread_info.h1
-rw-r--r--arch/s390/kernel/asm-offsets.c3
-rw-r--r--arch/s390/kernel/compat_signal.c2
-rw-r--r--arch/s390/kernel/entry.S28
-rw-r--r--arch/s390/kernel/entry64.S30
-rw-r--r--arch/s390/kernel/ptrace.c51
-rw-r--r--arch/s390/kernel/signal.c107
-rw-r--r--include/linux/elf.h1
10 files changed, 142 insertions, 91 deletions
diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h
index 62fd80c..93c907b 100644
--- a/arch/s390/include/asm/ptrace.h
+++ b/arch/s390/include/asm/ptrace.h
@@ -328,8 +328,7 @@ struct pt_regs
psw_t psw;
unsigned long gprs[NUM_GPRS];
unsigned long orig_gpr2;
- unsigned short ilc;
- unsigned short svcnr;
+ unsigned int svc_code;
};
/*
@@ -487,6 +486,8 @@ typedef struct
#define PTRACE_POKETEXT_AREA 0x5004
#define PTRACE_POKEDATA_AREA 0x5005
#define PTRACE_GET_LAST_BREAK 0x5006
+#define PTRACE_PEEK_SYSTEM_CALL 0x5007
+#define PTRACE_POKE_SYSTEM_CALL 0x5008
/*
* PT_PROT definition is loosely based on hppa bsd definition in
diff --git a/arch/s390/include/asm/syscall.h b/arch/s390/include/asm/syscall.h
index 5c0246b..614267f 100644
--- a/arch/s390/include/asm/syscall.h
+++ b/arch/s390/include/asm/syscall.h
@@ -13,6 +13,7 @@
#define _ASM_SYSCALL_H 1
#include <linux/sched.h>
+#include <linux/err.h>
#include <asm/ptrace.h>
/*
@@ -25,7 +26,7 @@ extern const unsigned int sys_call_table[];
static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
{
- return regs->svcnr ? regs->svcnr : -1;
+ return regs->svc_code ? (regs->svc_code & 0xffff) : -1;
}
static inline void syscall_rollback(struct task_struct *task,
@@ -37,7 +38,7 @@ static inline void syscall_rollback(struct task_struct *task,
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
- return (regs->gprs[2] >= -4096UL) ? -regs->gprs[2] : 0;
+ return IS_ERR_VALUE(regs->gprs[2]) ? regs->gprs[2] : 0;
}
static inline long syscall_get_return_value(struct task_struct *task,
diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h
index f9a9a10..0c4788e 100644
--- a/arch/s390/include/asm/thread_info.h
+++ b/arch/s390/include/asm/thread_info.h
@@ -48,6 +48,7 @@ struct thread_info {
unsigned int cpu; /* current CPU */
int preempt_count; /* 0 => preemptable, <0 => BUG */
struct restart_block restart_block;
+ unsigned int system_call;
__u64 user_timer;
__u64 system_timer;
unsigned long last_break; /* last breaking-event-address. */
diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index 1140035..7513187 100644
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -45,8 +45,7 @@ int main(void)
DEFINE(__PT_PSW, offsetof(struct pt_regs, psw));
DEFINE(__PT_GPRS, offsetof(struct pt_regs, gprs));
DEFINE(__PT_ORIG_GPR2, offsetof(struct pt_regs, orig_gpr2));
- DEFINE(__PT_ILC, offsetof(struct pt_regs, ilc));
- DEFINE(__PT_SVCNR, offsetof(struct pt_regs, svcnr));
+ DEFINE(__PT_SVC_CODE, offsetof(struct pt_regs, svc_code));
DEFINE(__PT_SIZE, sizeof(struct pt_regs));
BLANK();
DEFINE(__SF_BACKCHAIN, offsetof(struct stack_frame, back_chain));
diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c
index a9a285b..d7c8e54 100644
--- a/arch/s390/kernel/compat_signal.c
+++ b/arch/s390/kernel/compat_signal.c
@@ -342,7 +342,7 @@ static int restore_sigregs32(struct pt_regs *regs,_sigregs32 __user *sregs)
return err;
restore_fp_regs(&current->thread.fp_regs);
- regs->svcnr = 0; /* disable syscall checks */
+ regs->svc_code = 0; /* disable syscall checks */
return 0;
}
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 195387a..afe3685 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -43,8 +43,7 @@ SP_R13 = STACK_FRAME_OVERHEAD + __PT_GPRS + 52
SP_R14 = STACK_FRAME_OVERHEAD + __PT_GPRS + 56
SP_R15 = STACK_FRAME_OVERHEAD + __PT_GPRS + 60
SP_ORIG_R2 = STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
-SP_ILC = STACK_FRAME_OVERHEAD + __PT_ILC
-SP_SVCNR = STACK_FRAME_OVERHEAD + __PT_SVCNR
+SP_SVC_CODE = STACK_FRAME_OVERHEAD + __PT_SVC_CODE
SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE
_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
@@ -229,7 +228,7 @@ sysc_saveall:
SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SAVE_AREA
mvc SP_PSW(8,%r15),__LC_SVC_OLD_PSW
- mvc SP_ILC(4,%r15),__LC_SVC_ILC
+ mvc SP_SVC_CODE(4,%r15),__LC_SVC_ILC
l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
sysc_vtime:
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
@@ -239,12 +238,12 @@ sysc_update:
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
sysc_do_svc:
xr %r7,%r7
- icm %r7,3,SP_SVCNR(%r15) # load svc number and test for svc 0
+ icm %r7,3,SP_SVC_CODE+2(%r15)# load svc number and test for svc 0
bnz BASED(sysc_nr_ok) # svc number > 0
# svc 0: system call number in %r1
cl %r1,BASED(.Lnr_syscalls)
bnl BASED(sysc_nr_ok)
- sth %r1,SP_SVCNR(%r15)
+ sth %r1,SP_SVC_CODE+2(%r15)
lr %r7,%r1 # copy svc number to %r7
sysc_nr_ok:
sll %r7,2 # svc number *4
@@ -335,10 +334,11 @@ sysc_notify_resume:
#
sysc_restart:
ni __TI_flags+3(%r12),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
- l %r7,SP_R2(%r15) # load new svc number
- mvc SP_R2(4,%r15),SP_ORIG_R2(%r15) # restore first argument
lm %r2,%r6,SP_R2(%r15) # load svc arguments
- sth %r7,SP_SVCNR(%r15)
+ xr %r7,%r7 # svc 0 returns -ENOSYS
+ clc SP_SVC_CODE+2(%r15),BASED(.Lnr_syscalls+2)
+ bnl BASED(sysc_nr_ok) # invalid svc number -> do svc 0
+ icm %r7,3,SP_SVC_CODE+2(%r15)# load new svc number
b BASED(sysc_nr_ok) # restart svc
#
@@ -346,7 +346,7 @@ sysc_restart:
#
sysc_singlestep:
ni __TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
- xc SP_SVCNR(2,%r15),SP_SVCNR(%r15) # clear svc number
+ xc SP_SVC_CODE(4,%r15),SP_SVC_CODE(%r15) # clear svc code
la %r2,SP_PTREGS(%r15) # address of register-save area
l %r1,BASED(.Lhandle_per) # load adr. of per handler
la %r14,BASED(sysc_return) # load adr. of system return
@@ -361,7 +361,7 @@ sysc_tracesys:
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,0
xr %r0,%r0
- icm %r0,3,SP_SVCNR(%r15)
+ icm %r0,3,SP_SVC_CODE(%r15)
st %r0,SP_R2(%r15)
basr %r14,%r1
cl %r2,BASED(.Lnr_syscalls)
@@ -454,7 +454,7 @@ ENTRY(pgm_check_handler)
bnz BASED(pgm_per) # got per exception -> special case
SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SAVE_AREA
- xc SP_ILC(4,%r15),SP_ILC(%r15)
+ xc SP_SVC_CODE(4,%r15),SP_SVC_CODE(%r15)
mvc SP_PSW(8,%r15),__LC_PGM_OLD_PSW
l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
@@ -531,7 +531,7 @@ pgm_svcper:
SAVE_ALL_PGM __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SAVE_AREA
mvc SP_PSW(8,%r15),__LC_SVC_OLD_PSW
- mvc SP_ILC(4,%r15),__LC_SVC_ILC
+ mvc SP_SVC_CODE(4,%r15),__LC_SVC_ILC
l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
@@ -550,7 +550,7 @@ pgm_svcper:
#
kernel_per:
REENABLE_IRQS
- xc SP_SVCNR(2,%r15),SP_SVCNR(%r15)
+ xc SP_SVC_CODE(4,%r15),SP_SVC_CODE(%r15)
la %r2,SP_PTREGS(%r15) # address of register-save area
l %r1,BASED(.Lhandle_per) # load adr. of per handler
basr %r14,%r1 # branch to do_single_step
@@ -966,7 +966,7 @@ cleanup_system_call:
st %r15,12(%r12)
CREATE_STACK_FRAME __LC_SAVE_AREA
mvc SP_PSW(8,%r15),__LC_SVC_OLD_PSW
- mvc SP_ILC(4,%r15),__LC_SVC_ILC
+ mvc SP_SVC_CODE(4,%r15),__LC_SVC_ILC
mvc 0(4,%r12),__LC_THREAD_INFO
cleanup_vtime:
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+12)
diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 3257f7f..7ff07d3 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -43,8 +43,7 @@ SP_R13 = STACK_FRAME_OVERHEAD + __PT_GPRS + 104
SP_R14 = STACK_FRAME_OVERHEAD + __PT_GPRS + 112
SP_R15 = STACK_FRAME_OVERHEAD + __PT_GPRS + 120
SP_ORIG_R2 = STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
-SP_ILC = STACK_FRAME_OVERHEAD + __PT_ILC
-SP_SVCNR = STACK_FRAME_OVERHEAD + __PT_SVCNR
+SP_SVC_CODE = STACK_FRAME_OVERHEAD + __PT_SVC_CODE
SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE
STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
@@ -250,7 +249,7 @@ sysc_saveall:
SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SAVE_AREA
mvc SP_PSW(16,%r15),__LC_SVC_OLD_PSW
- mvc SP_ILC(4,%r15),__LC_SVC_ILC
+ mvc SP_SVC_CODE(4,%r15),__LC_SVC_ILC
lg %r12,__LC_THREAD_INFO # load pointer to thread_info struct
sysc_vtime:
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
@@ -260,14 +259,14 @@ sysc_update:
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
LAST_BREAK
sysc_do_svc:
- llgh %r7,SP_SVCNR(%r15)
+ llgh %r7,SP_SVC_CODE+2(%r15)
slag %r7,%r7,2 # shift and test for svc 0
jnz sysc_nr_ok
# svc 0: system call number in %r1
llgfr %r1,%r1 # clear high word in r1
cghi %r1,NR_syscalls
jnl sysc_nr_ok
- sth %r1,SP_SVCNR(%r15)
+ sth %r1,SP_SVC_CODE+2(%r15)
slag %r7,%r1,2 # shift and test for svc 0
sysc_nr_ok:
larl %r10,sys_call_table
@@ -358,11 +357,12 @@ sysc_notify_resume:
#
sysc_restart:
ni __TI_flags+7(%r12),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
- lg %r7,SP_R2(%r15) # load new svc number
- mvc SP_R2(8,%r15),SP_ORIG_R2(%r15) # restore first argument
lmg %r2,%r6,SP_R2(%r15) # load svc arguments
- sth %r7,SP_SVCNR(%r15)
- slag %r7,%r7,2
+ lghi %r7,0 # svc 0 returns -ENOSYS
+ lh %r1,SP_SVC_CODE+2(%r15) # load new svc number
+ cghi %r1,NR_syscalls
+ jnl sysc_nr_ok # invalid svc number -> do svc 0
+ slag %r7,%r1,2
j sysc_nr_ok # restart svc
#
@@ -370,7 +370,7 @@ sysc_restart:
#
sysc_singlestep:
ni __TI_flags+7(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
- xc SP_SVCNR(2,%r15),SP_SVCNR(%r15) # clear svc number
+ xc SP_SVC_CODE(4,%r15),SP_SVC_CODE(%r15) # clear svc code
la %r2,SP_PTREGS(%r15) # address of register-save area
larl %r14,sysc_return # load adr. of system return
jg do_per_trap
@@ -382,7 +382,7 @@ sysc_singlestep:
sysc_tracesys:
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,0
- llgh %r0,SP_SVCNR(%r15)
+ llgh %r0,SP_SVC_CODE+2(%r15)
stg %r0,SP_R2(%r15)
brasl %r14,do_syscall_trace_enter
lghi %r0,NR_syscalls
@@ -470,7 +470,7 @@ ENTRY(pgm_check_handler)
jnz pgm_per # got per exception -> special case
SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SAVE_AREA
- xc SP_ILC(4,%r15),SP_ILC(%r15)
+ xc SP_SVC_CODE(4,%r15),SP_SVC_CODE(%r15)
mvc SP_PSW(16,%r15),__LC_PGM_OLD_PSW
lg %r12,__LC_THREAD_INFO # load pointer to thread_info struct
HANDLE_SIE_INTERCEPT
@@ -551,7 +551,7 @@ pgm_svcper:
SAVE_ALL_PGM __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SAVE_AREA
mvc SP_PSW(16,%r15),__LC_SVC_OLD_PSW
- mvc SP_ILC(4,%r15),__LC_SVC_ILC
+ mvc SP_SVC_CODE(4,%r15),__LC_SVC_ILC
lg %r12,__LC_THREAD_INFO # load pointer to thread_info struct
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
@@ -571,7 +571,7 @@ pgm_svcper:
#
kernel_per:
REENABLE_IRQS
- xc SP_SVCNR(2,%r15),SP_SVCNR(%r15) # clear svc number
+ xc SP_SVC_CODE(4,%r15),SP_SVC_CODE(%r15) # clear svc number
la %r2,SP_PTREGS(%r15) # address of register-save area
brasl %r14,do_per_trap
j pgm_exit
@@ -973,7 +973,7 @@ cleanup_system_call:
stg %r11,0(%r12)
CREATE_STACK_FRAME __LC_SAVE_AREA
mvc SP_PSW(16,%r15),__LC_SVC_OLD_PSW
- mvc SP_ILC(4,%r15),__LC_SVC_ILC
+ mvc SP_SVC_CODE(4,%r15),__LC_SVC_ILC
mvc 8(8,%r12),__LC_THREAD_INFO
cleanup_vtime:
clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+24)
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index ae0e14b..bae1cc4 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -42,6 +42,7 @@ enum s390_regset {
REGSET_GENERAL,
REGSET_FP,
REGSET_LAST_BREAK,
+ REGSET_SYSTEM_CALL,
REGSET_GENERAL_EXTENDED,
};
@@ -303,6 +304,13 @@ static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
high order bit but older gdb's rely on it */
data |= PSW_ADDR_AMODE;
#endif
+ if (addr == (addr_t) &dummy->regs.psw.addr)
+ /*
+ * The debugger changed the instruction address,
+ * reset system call restart, see signal.c:do_signal
+ */
+ task_thread_info(child)->system_call = 0;
+
*(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
} else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
@@ -610,6 +618,11 @@ static int __poke_user_compat(struct task_struct *child,
/* Build a 64 bit psw address from 31 bit address. */
task_pt_regs(child)->psw.addr =
(__u64) tmp & PSW32_ADDR_INSN;
+ /*
+ * The debugger changed the instruction address,
+ * reset system call restart, see signal.c:do_signal
+ */
+ task_thread_info(child)->system_call = 0;
} else {
/* gpr 0-15 */
*(__u32*)((addr_t) &task_pt_regs(child)->psw
@@ -737,7 +750,7 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
* debugger stored an invalid system call number. Skip
* the system call and the system call restart handling.
*/
- regs->svcnr = 0;
+ regs->svc_code = 0;
ret = -1;
}
@@ -899,6 +912,26 @@ static int s390_last_break_get(struct task_struct *target,
#endif
+static int s390_system_call_get(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ unsigned int *data = &task_thread_info(target)->system_call;
+ return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ data, 0, sizeof(unsigned int));
+}
+
+static int s390_system_call_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ unsigned int *data = &task_thread_info(target)->system_call;
+ return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ data, 0, sizeof(unsigned int));
+}
+
static const struct user_regset s390_regsets[] = {
[REGSET_GENERAL] = {
.core_note_type = NT_PRSTATUS,
@@ -925,6 +958,14 @@ static const struct user_regset s390_regsets[] = {
.get = s390_last_break_get,
},
#endif
+ [REGSET_SYSTEM_CALL] = {
+ .core_note_type = NT_S390_SYSTEM_CALL,
+ .n = 1,
+ .size = sizeof(unsigned int),
+ .align = sizeof(unsigned int),
+ .get = s390_system_call_get,
+ .set = s390_system_call_set,
+ },
};
static const struct user_regset_view user_s390_view = {
@@ -1104,6 +1145,14 @@ static const struct user_regset s390_compat_regsets[] = {
.align = sizeof(long),
.get = s390_compat_last_break_get,
},
+ [REGSET_SYSTEM_CALL] = {
+ .core_note_type = NT_S390_SYSTEM_CALL,
+ .n = 1,
+ .size = sizeof(compat_uint_t),
+ .align = sizeof(compat_uint_t),
+ .get = s390_system_call_get,
+ .set = s390_system_call_set,
+ },
[REGSET_GENERAL_EXTENDED] = {
.core_note_type = NT_S390_HIGH_GPRS,
.n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 9a40e1c..e751cab 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -30,6 +30,7 @@
#include <asm/ucontext.h>
#include <asm/uaccess.h>
#include <asm/lowcore.h>
+#include <asm/compat.h>
#include "entry.h"
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
@@ -156,7 +157,7 @@ static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
current->thread.fp_regs.fpc &= FPC_VALID_MASK;
restore_fp_regs(&current->thread.fp_regs);
- regs->svcnr = 0; /* disable syscall checks */
+ regs->svc_code = 0; /* disable syscall checks */
return 0;
}
@@ -401,7 +402,6 @@ static int handle_signal(unsigned long sig, struct k_sigaction *ka,
*/
void do_signal(struct pt_regs *regs)
{
- unsigned long retval = 0, continue_addr = 0, restart_addr = 0;
siginfo_t info;
int signr;
struct k_sigaction ka;
@@ -421,54 +421,43 @@ void do_signal(struct pt_regs *regs)
else
oldset = &current->blocked;
- /* Are we from a system call? */
- if (regs->svcnr) {
- continue_addr = regs->psw.addr;
- restart_addr = continue_addr - regs->ilc;
- retval = regs->gprs[2];
-
- /* Prepare for system call restart. We do this here so that a
- debugger will see the already changed PSW. */
- switch (retval) {
- case -ERESTARTNOHAND:
- case -ERESTARTSYS:
- case -ERESTARTNOINTR:
- regs->gprs[2] = regs->orig_gpr2;
- regs->psw.addr = restart_addr;
- break;
- case -ERESTART_RESTARTBLOCK:
- regs->gprs[2] = -EINTR;
- }
- regs->svcnr = 0; /* Don't deal with this again. */
- }
-
- /* Get signal to deliver. When running under ptrace, at this point
- the debugger may change all our registers ... */
+ /*
+ * Get signal to deliver. When running under ptrace, at this point
+ * the debugger may change all our registers, including the system
+ * call information.
+ */
+ current_thread_info()->system_call = regs->svc_code;
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
-
- /* Depending on the signal settings we may need to revert the
- decision to restart the system call. */
- if (signr > 0 && regs->psw.addr == restart_addr) {
- if (retval == -ERESTARTNOHAND
- || (retval == -ERESTARTSYS
- && !(current->sighand->action[signr-1].sa.sa_flags
- & SA_RESTART))) {
- regs->gprs[2] = -EINTR;
- regs->psw.addr = continue_addr;
- }
- }
+ regs->svc_code = current_thread_info()->system_call;
if (signr > 0) {
/* Whee! Actually deliver the signal. */
- int ret;
-#ifdef CONFIG_COMPAT
- if (is_compat_task()) {
- ret = handle_signal32(signr, &ka, &info, oldset, regs);
- }
- else
-#endif
- ret = handle_signal(signr, &ka, &info, oldset, regs);
- if (!ret) {
+ if (regs->svc_code > 0) {
+ /* Check for system call restarting. */
+ switch (regs->gprs[2]) {
+ case -ERESTART_RESTARTBLOCK:
+ case -ERESTARTNOHAND:
+ regs->gprs[2] = -EINTR;
+ break;
+ case -ERESTARTSYS:
+ if (!(ka.sa.sa_flags & SA_RESTART)) {
+ regs->gprs[2] = -EINTR;
+ break;
+ }
+ /* fallthrough */
+ case -ERESTARTNOINTR:
+ regs->gprs[2] = regs->orig_gpr2;
+ regs->psw.addr = regs->psw.addr -
+ (regs->svc_code >> 16);
+ break;
+ }
+ /* No longer in a system call */
+ regs->svc_code = 0;
+ }
+
+ if ((is_compat_task() ?
+ handle_signal32(signr, &ka, &info, oldset, regs) :
+ handle_signal(signr, &ka, &info, oldset, regs)) == 0) {
/*
* A signal was successfully delivered; the saved
* sigmask will have been stored in the signal frame,
@@ -482,11 +471,28 @@ void do_signal(struct pt_regs *regs)
* Let tracing know that we've done the handler setup.
*/
tracehook_signal_handler(signr, &info, &ka, regs,
- test_thread_flag(TIF_SINGLE_STEP));
+ test_thread_flag(TIF_SINGLE_STEP));
}
return;
}
+ /* No handlers present - check for system call restart */
+ if (regs->svc_code > 0) {
+ switch (regs->gprs[2]) {
+ case -ERESTART_RESTARTBLOCK:
+ /* Restart with sys_restart_syscall */
+ regs->svc_code = __NR_restart_syscall;
+ /* fallthrough */
+ case -ERESTARTNOHAND:
+ case -ERESTARTSYS:
+ case -ERESTARTNOINTR:
+ /* Restart system call with magic TIF bit. */
+ regs->gprs[2] = regs->orig_gpr2;
+ set_thread_flag(TIF_RESTART_SVC);
+ break;
+ }
+ }
+
/*
* If there's no signal to deliver, we just put the saved sigmask back.
*/
@@ -494,13 +500,6 @@ void do_signal(struct pt_regs *regs)
clear_thread_flag(TIF_RESTORE_SIGMASK);
sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
}
-
- /* Restart a different system call. */
- if (retval == -ERESTART_RESTARTBLOCK
- && regs->psw.addr == continue_addr) {
- regs->gprs[2] = __NR_restart_syscall;
- set_thread_flag(TIF_RESTART_SVC);
- }
}
void do_notify_resume(struct pt_regs *regs)
diff --git a/include/linux/elf.h b/include/linux/elf.h
index 110821c..31f0508 100644
--- a/include/linux/elf.h
+++ b/include/linux/elf.h
@@ -395,6 +395,7 @@ typedef struct elf64_shdr {
#define NT_S390_CTRS 0x304 /* s390 control registers */
#define NT_S390_PREFIX 0x305 /* s390 prefix register */
#define NT_S390_LAST_BREAK 0x306 /* s390 breaking event address */
+#define NT_S390_SYSTEM_CALL 0x307 /* s390 system call restart data */
#define NT_ARM_VFP 0x400 /* ARM VFP/NEON registers */
OpenPOWER on IntegriCloud