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author | Sven Schnelle <svens@linux.ibm.com> | 2020-11-21 13:14:56 +0300 |
---|---|---|
committer | Vasily Gorbik <gor@linux.ibm.com> | 2021-01-19 14:29:26 +0300 |
commit | 56e62a73702836017564eaacd5212e4d0fa1c01d (patch) | |
tree | f99a6cb9175ddddc37f36ad538555fbb5c606a6c /arch/s390/include/asm/lowcore.h | |
parent | ac94a2911e84a7b3d29d725f8f43b07db1c916f2 (diff) | |
download | linux-56e62a73702836017564eaacd5212e4d0fa1c01d.tar.xz |
s390: convert to generic entry
This patch converts s390 to use the generic entry infrastructure from
kernel/entry/*.
There are a few special things on s390:
- PIF_PER_TRAP is moved to TIF_PER_TRAP as the generic code doesn't
know about our PIF flags in exit_to_user_mode_loop().
- The old code had several ways to restart syscalls:
a) PIF_SYSCALL_RESTART, which was only set during execve to force a
restart after upgrading a process (usually qemu-kvm) to pgste page
table extensions.
b) PIF_SYSCALL, which is set by do_signal() to indicate that the
current syscall should be restarted. This is changed so that
do_signal() now also uses PIF_SYSCALL_RESTART. Continuing to use
PIF_SYSCALL doesn't work with the generic code, and changing it
to PIF_SYSCALL_RESTART makes PIF_SYSCALL and PIF_SYSCALL_RESTART
more unique.
- On s390 calling sys_sigreturn or sys_rt_sigreturn is implemented by
executing a svc instruction on the process stack which causes a fault.
While handling that fault the fault code sets PIF_SYSCALL to hand over
processing to the syscall code on exit to usermode.
The patch introduces PIF_SYSCALL_RET_SET, which is set if ptrace sets
a return value for a syscall. The s390x ptrace ABI uses r2 both for the
syscall number and return value, so ptrace cannot set the syscall number +
return value at the same time. The flag makes handling that a bit easier.
do_syscall() will just skip executing the syscall if PIF_SYSCALL_RET_SET
is set.
CONFIG_DEBUG_ASCE was removd in favour of the generic CONFIG_DEBUG_ENTRY.
CR1/7/13 will be checked both on kernel entry and exit to contain the
correct asces.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch/s390/include/asm/lowcore.h')
-rw-r--r-- | arch/s390/include/asm/lowcore.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h index 69ce9191eaf1..4d65c8e4e6d0 100644 --- a/arch/s390/include/asm/lowcore.h +++ b/arch/s390/include/asm/lowcore.h @@ -81,8 +81,8 @@ struct lowcore { psw_t return_mcck_psw; /* 0x02a0 */ /* CPU accounting and timing values. */ - __u64 sync_enter_timer; /* 0x02b0 */ - __u64 async_enter_timer; /* 0x02b8 */ + __u64 sys_enter_timer; /* 0x02b0 */ + __u8 pad_0x02b8[0x02c0-0x02b8]; /* 0x02b8 */ __u64 mcck_enter_timer; /* 0x02c0 */ __u64 exit_timer; /* 0x02c8 */ __u64 user_timer; /* 0x02d0 */ |