From: Baoquan He Date: Wed, 14 Feb 2018 13:46:52 +0800 Subject: x86/apic: Split disable_IO_APIC() into two functions to fix CONFIG_KEXEC_JUMP=y Git-commit: 3c9e76dbea004b2c7c3ce872022ceaf5ff0dae79 Patch-mainline: v4.17-rc1 References: bsc#1110006 Split following patches disable_IO_APIC() will be broken up into clear_IO_APIC() and restore_boot_irq_mode(). These two functions will be called separately where they are needed to fix a regression introduced by: 522e66464467 ("x86/apic: Disable I/O APIC before shutdown of the local APIC"). While the CONFIG_KEXEC_JUMP=y code doesn't call lapic_shutdown() before jump like kexec/kdump, so it's not impacted by commit 522e66464467. Hence here change clear_IO_APIC() as public, and replace disable_IO_APIC() with clear_IO_APIC() and restore_boot_irq_mode() to keep CONFIG_KEXEC_JUMP=y code unchanged in essence. No functional change. Signed-off-by: Baoquan He Reviewed-by: Eric W. Biederman Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: douly.fnst@cn.fujitsu.com Cc: joro@8bytes.org Cc: prarit@redhat.com Cc: uobergfe@redhat.com Link: http://lkml.kernel.org/r/20180214054656.3780-3-bhe@redhat.com [ Rewrote the changelog. ] Signed-off-by: Ingo Molnar Acked-by: Joerg Roedel --- arch/x86/include/asm/io_apic.h | 1 + arch/x86/kernel/apic/io_apic.c | 2 +- arch/x86/kernel/machine_kexec_32.c | 3 ++- arch/x86/kernel/machine_kexec_64.c | 3 ++- 4 files changed, 6 insertions(+), 3 deletions(-) --- a/arch/x86/include/asm/io_apic.h +++ b/arch/x86/include/asm/io_apic.h @@ -192,6 +192,7 @@ static inline unsigned int io_apic_read( extern void setup_IO_APIC(void); extern void enable_IO_APIC(void); extern void disable_IO_APIC(void); +extern void clear_IO_APIC(void); extern void restore_boot_irq_mode(void); extern void setup_ioapic_dest(void); extern int IO_APIC_get_PCI_irq_vector(int bus, int devfn, int pin); --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -586,7 +586,7 @@ static void clear_IO_APIC_pin(unsigned i mpc_ioapic_id(apic), pin); } -static void clear_IO_APIC (void) +void clear_IO_APIC (void) { int apic, pin; --- a/arch/x86/kernel/machine_kexec_32.c +++ b/arch/x86/kernel/machine_kexec_32.c @@ -213,7 +213,8 @@ void machine_kexec(struct kimage *image) * one form or other. kexec jump path also need * one. */ - disable_IO_APIC(); + clear_IO_APIC(); + restore_boot_irq_mode(); #endif } --- a/arch/x86/kernel/machine_kexec_64.c +++ b/arch/x86/kernel/machine_kexec_64.c @@ -297,7 +297,8 @@ void machine_kexec(struct kimage *image) * one form or other. kexec jump path also need * one. */ - disable_IO_APIC(); + clear_IO_APIC(); + restore_boot_irq_mode(); #endif }