iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

s390/entry: Move SIE indicator flag to thread info

Browse Source 
CIF_SIE indicates if a thread is running in SIE context. This is the
state of a thread and not the CPU. Therefore move this indicator to
thread info.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Heiko Carstens 2024-07-22 15:41:12 +02:00 committed by Vasily Gorbik
parent 213400c4af
commit fc8eac33ad
4 changed files with 14 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/s390/include/asm/processor.h
View File

@ -14,13 +14,11 @@
#include <linux/bits.h>
#define CIF_SIE 0 /* CPU needs SIE exit cleanup */
#define CIF_NOHZ_DELAY 2 /* delay HZ disable for a tick */
#define CIF_ENABLED_WAIT 5 /* in enabled wait state */
#define CIF_MCCK_GUEST 6 /* machine check happening in guest */
#define CIF_DEDICATED_CPU 7 /* this CPU is dedicated */
#define _CIF_SIE BIT(CIF_SIE)
#define _CIF_NOHZ_DELAY BIT(CIF_NOHZ_DELAY)
#define _CIF_ENABLED_WAIT BIT(CIF_ENABLED_WAIT)
#define _CIF_MCCK_GUEST BIT(CIF_MCCK_GUEST)

1
arch/s390/include/asm/thread_info.h
View File

@ -40,6 +40,7 @@ struct thread_info {
unsigned long flags; /* low level flags */
unsigned long syscall_work; /* SYSCALL_WORK_ flags */
unsigned int cpu; /* current CPU */
unsigned char sie; /* running in SIE context */
};
/*

1
arch/s390/kernel/asm-offsets.c
View File

@ -28,6 +28,7 @@ int main(void)
BLANK();
/* thread info offsets */
OFFSET(__TI_flags, task_struct, thread_info.flags);
OFFSET(__TI_sie, task_struct, thread_info.sie);
BLANK();
/* pt_regs offsets */
OFFSET(__PT_PSW, pt_regs, psw);

20
arch/s390/kernel/entry.S
View File

@ -123,7 +123,8 @@ _LPP_OFFSET = __LC_LPP
lg %r9,\sie_control # get control block pointer
ni __SIE_PROG0C+3(%r9),0xfe # no longer in SIE
lctlg %c1,%c1,__LC_KERNEL_ASCE # load primary asce
ni __LC_CPU_FLAGS+7,255-_CIF_SIE
lg %r9,__LC_CURRENT
mvi __TI_sie(%r9),0
larl %r9,sie_exit # skip forward to sie_exit
.endm
#endif
@ -183,15 +184,15 @@ SYM_FUNC_END(__switch_to_asm)
*/
SYM_FUNC_START(__sie64a)
stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers
lg %r12,__LC_CURRENT
lg %r14,__LC_CURRENT
stg %r2,__SF_SIE_CONTROL_PHYS(%r15) # save sie block physical..
stg %r3,__SF_SIE_CONTROL(%r15) # ...and virtual addresses
stg %r4,__SF_SIE_SAVEAREA(%r15) # save guest register save area
stg %r5,__SF_SIE_GUEST_ASCE(%r15) # save guest asce
xc __SF_SIE_REASON(8,%r15),__SF_SIE_REASON(%r15) # reason code = 0
mvc __SF_SIE_FLAGS(8,%r15),__TI_flags(%r12) # copy thread flags
mvc __SF_SIE_FLAGS(8,%r15),__TI_flags(%r14) # copy thread flags
lmg %r0,%r13,0(%r4) # load guest gprs 0-13
oi __LC_CPU_FLAGS+7,_CIF_SIE
mvi __TI_sie(%r14),1
lctlg %c1,%c1,__SF_SIE_GUEST_ASCE(%r15) # load primary asce
lg %r14,__SF_SIE_CONTROL(%r15) # get control block pointer
oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now
@ -211,7 +212,8 @@ SYM_FUNC_START(__sie64a)
lg %r14,__SF_SIE_CONTROL(%r15) # get control block pointer
ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
lctlg %c1,%c1,__LC_KERNEL_ASCE # load primary asce
ni __LC_CPU_FLAGS+7,255-_CIF_SIE
lg %r14,__LC_CURRENT
mvi __TI_sie(%r14),0
# some program checks are suppressing. C code (e.g. do_protection_exception)
# will rewind the PSW by the ILC, which is often 4 bytes in case of SIE. There
# are some corner cases (e.g. runtime instrumentation) where ILC is unpredictable.
@ -394,7 +396,8 @@ SYM_CODE_START(\name)
tmhh %r8,0x0001 # interrupting from user ?
jnz 1f
#if IS_ENABLED(CONFIG_KVM)
TSTMSK __LC_CPU_FLAGS,_CIF_SIE
lg %r10,__LC_CURRENT
tm __TI_sie(%r10),0xff
jz 0f
BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST
SIEEXIT __SF_SIE_CONTROL(%r15)
@ -469,9 +472,10 @@ SYM_CODE_START(mcck_int_handler)
TSTMSK __LC_MCCK_CODE,MCCK_CODE_PSW_IA_VALID
jno .Lmcck_panic
#if IS_ENABLED(CONFIG_KVM)
TSTMSK __LC_CPU_FLAGS,_CIF_SIE
lg %r10,__LC_CURRENT
tm __TI_sie(%r10),0xff
jz .Lmcck_user
# Need to compare the address instead of a CIF_SIE* flag.
# Need to compare the address instead of __TI_SIE flag.
# Otherwise there would be a race between setting the flag
# and entering SIE (or leaving and clearing the flag). This
# would cause machine checks targeted at the guest to be