diff options
| author | Heiko Carstens <hca@linux.ibm.com> | 2025-01-20 11:53:42 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-02-08 10:02:14 +0100 |
| commit | 62ac92cc9163c3479bc5a55723e3bfaf7694c2bb (patch) | |
| tree | c9dffb131f61e7dce3e2da73f1e5cd20b57d1fcd /arch | |
| parent | a24764cacb81ab870de742d1bd05637da7e02dd4 (diff) | |
| download | linux-62ac92cc9163c3479bc5a55723e3bfaf7694c2bb.tar.gz linux-62ac92cc9163c3479bc5a55723e3bfaf7694c2bb.tar.bz2 linux-62ac92cc9163c3479bc5a55723e3bfaf7694c2bb.zip | |
s390/sclp: Initialize sclp subsystem via arch_cpu_finalize_init()
[ Upstream commit 3bcc8a1af581af152d43e42b53db3534018301b5 ]
With the switch to GENERIC_CPU_DEVICES an early call to the sclp subsystem
was added to smp_prepare_cpus(). This will usually succeed since the sclp
subsystem is implicitly initialized early enough if an sclp based console
is present.
If no such console is present the initialization happens with an
arch_initcall(); in such cases calls to the sclp subsystem will fail.
For CPU detection this means that the fallback sigp loop will be used
permanently to detect CPUs instead of the preferred READ_CPU_INFO sclp
request.
Fix this by adding an explicit early sclp_init() call via
arch_cpu_finalize_init().
Reported-by: Sheshu Ramanandan <sheshu.ramanandan@ibm.com>
Fixes: 4a39f12e753d ("s390/smp: Switch to GENERIC_CPU_DEVICES")
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/s390/Kconfig | 1 | ||||
| -rw-r--r-- | arch/s390/include/asm/sclp.h | 1 | ||||
| -rw-r--r-- | arch/s390/kernel/setup.c | 5 |
3 files changed, 7 insertions, 0 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 0077969170e8..83b1d7bbd888 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -72,6 +72,7 @@ config S390 select ARCH_ENABLE_MEMORY_HOTPLUG if SPARSEMEM select ARCH_ENABLE_MEMORY_HOTREMOVE select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 + select ARCH_HAS_CPU_FINALIZE_INIT select ARCH_HAS_CURRENT_STACK_POINTER select ARCH_HAS_DEBUG_VIRTUAL select ARCH_HAS_DEBUG_VM_PGTABLE diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h index eb00fa1771da..ad17d91ad2e6 100644 --- a/arch/s390/include/asm/sclp.h +++ b/arch/s390/include/asm/sclp.h @@ -137,6 +137,7 @@ void sclp_early_printk(const char *s); void __sclp_early_printk(const char *s, unsigned int len); void sclp_emergency_printk(const char *s); +int sclp_init(void); int sclp_early_get_memsize(unsigned long *mem); int sclp_early_get_hsa_size(unsigned long *hsa_size); int _sclp_get_core_info(struct sclp_core_info *info); diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index a3fea683b227..99f165726ca9 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -1006,3 +1006,8 @@ void __init setup_arch(char **cmdline_p) /* Add system specific data to the random pool */ setup_randomness(); } + +void __init arch_cpu_finalize_init(void) +{ + sclp_init(); +} |