[ Upstream commit cf1489984641369611556bf00c48f945c77bcf02 ]
To be able to switch off specific CPU alternatives with kernel parameters make a copy of the facility bit mask provided by STFLE and use the copy for the decision to apply an alternative.
Reviewed-by: David Hildenbrand david@redhat.com Reviewed-by: Cornelia Huck cohuck@redhat.com Signed-off-by: Martin Schwidefsky schwidefsky@de.ibm.com --- arch/s390/include/asm/facility.h | 18 ++++++++++++++++++ arch/s390/include/asm/lowcore.h | 3 ++- arch/s390/kernel/alternative.c | 3 ++- arch/s390/kernel/early.c | 3 +++ arch/s390/kernel/setup.c | 4 +++- arch/s390/kernel/smp.c | 4 +++- 6 files changed, 31 insertions(+), 4 deletions(-)
diff --git a/arch/s390/include/asm/facility.h b/arch/s390/include/asm/facility.h index 09b406db7529..7a8a1457dbb8 100644 --- a/arch/s390/include/asm/facility.h +++ b/arch/s390/include/asm/facility.h @@ -17,6 +17,24 @@
#define MAX_FACILITY_BIT (256*8) /* stfle_fac_list has 256 bytes */
+static inline void __set_facility(unsigned long nr, void *facilities) +{ + unsigned char *ptr = (unsigned char *) facilities; + + if (nr >= MAX_FACILITY_BIT) + return; + ptr[nr >> 3] |= 0x80 >> (nr & 7); +} + +static inline void __clear_facility(unsigned long nr, void *facilities) +{ + unsigned char *ptr = (unsigned char *) facilities; + + if (nr >= MAX_FACILITY_BIT) + return; + ptr[nr >> 3] &= ~(0x80 >> (nr & 7)); +} + static inline int __test_facility(unsigned long nr, void *facilities) { unsigned char *ptr; diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h index 7b93b78f423c..d52e7efea7d6 100644 --- a/arch/s390/include/asm/lowcore.h +++ b/arch/s390/include/asm/lowcore.h @@ -150,7 +150,8 @@ struct lowcore { __u8 pad_0x0e20[0x0f00-0x0e20]; /* 0x0e20 */
/* Extended facility list */ - __u64 stfle_fac_list[32]; /* 0x0f00 */ + __u64 stfle_fac_list[16]; /* 0x0f00 */ + __u64 alt_stfle_fac_list[16]; /* 0x0f80 */ __u8 pad_0x1000[0x11b0-0x1000]; /* 0x1000 */
/* Pointer to vector register save area */ diff --git a/arch/s390/kernel/alternative.c b/arch/s390/kernel/alternative.c index 315986a06cf5..f5060af61176 100644 --- a/arch/s390/kernel/alternative.c +++ b/arch/s390/kernel/alternative.c @@ -74,7 +74,8 @@ static void __init_or_module __apply_alternatives(struct alt_instr *start, instr = (u8 *)&a->instr_offset + a->instr_offset; replacement = (u8 *)&a->repl_offset + a->repl_offset;
- if (!test_facility(a->facility)) + if (!__test_facility(a->facility, + S390_lowcore.alt_stfle_fac_list)) continue;
if (unlikely(a->instrlen % 2 || a->replacementlen % 2)) { diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c index 62578989c74d..171aaa221e4b 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -299,6 +299,9 @@ static noinline __init void setup_facility_list(void) { stfle(S390_lowcore.stfle_fac_list, ARRAY_SIZE(S390_lowcore.stfle_fac_list)); + memcpy(S390_lowcore.alt_stfle_fac_list, + S390_lowcore.stfle_fac_list, + sizeof(S390_lowcore.alt_stfle_fac_list)); }
static __init void detect_diag9c(void) diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index c3bdb3e80380..433b380896b9 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -336,7 +336,9 @@ static void __init setup_lowcore(void) lc->machine_flags = S390_lowcore.machine_flags; lc->stfl_fac_list = S390_lowcore.stfl_fac_list; memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list, - MAX_FACILITY_BIT/8); + sizeof(lc->stfle_fac_list)); + memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list, + sizeof(lc->alt_stfle_fac_list)); if (MACHINE_HAS_VX) lc->vector_save_area_addr = (unsigned long) &lc->vector_save_area; diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 35531fe1c5ea..63c8a840d56b 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -253,7 +253,9 @@ static void pcpu_prepare_secondary(struct pcpu *pcpu, int cpu) __ctl_store(lc->cregs_save_area, 0, 15); save_access_regs((unsigned int *) lc->access_regs_save_area); memcpy(lc->stfle_fac_list, S390_lowcore.stfle_fac_list, - MAX_FACILITY_BIT/8); + sizeof(lc->stfle_fac_list)); + memcpy(lc->alt_stfle_fac_list, S390_lowcore.alt_stfle_fac_list, + sizeof(lc->alt_stfle_fac_list)); }
static void pcpu_attach_task(struct pcpu *pcpu, struct task_struct *tsk)