Star64_linux/arch
Thomas Gleixner 7d65f9e806 x86/apic: Mark _all_ legacy interrupts when IO/APIC is missing
PIC interrupts do not support affinity setting and they can end up on
any online CPU. Therefore, it's required to mark the associated vectors
as system-wide reserved. Otherwise, the corresponding irq descriptors
are copied to the secondary CPUs but the vectors are not marked as
assigned or reserved. This works correctly for the IO/APIC case.

When the IO/APIC is disabled via config, kernel command line or lack of
enumeration then all legacy interrupts are routed through the PIC, but
nothing marks them as system-wide reserved vectors.

As a consequence, a subsequent allocation on a secondary CPU can result in
allocating one of these vectors, which triggers the BUG() in
apic_update_vector() because the interrupt descriptor slot is not empty.

Imran tried to work around that by marking those interrupts as allocated
when a CPU comes online. But that's wrong in case that the IO/APIC is
available and one of the legacy interrupts, e.g. IRQ0, has been switched to
PIC mode because then marking them as allocated will fail as they are
already marked as system vectors.

Stay consistent and update the legacy vectors after attempting IO/APIC
initialization and mark them as system vectors in case that no IO/APIC is
available.

Fixes: 69cde0004a ("x86/vector: Use matrix allocator for vector assignment")
Reported-by: Imran Khan <imran.f.khan@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20210519233928.2157496-1-imran.f.khan@oracle.com
2021-05-29 11:41:14 +02:00
..
alpha quota: Disable quotactl_path syscall 2021-05-17 14:39:56 +02:00
arc ARC: mm: Use max_high_pfn as a HIGHMEM zone border 2021-05-10 12:38:59 -07:00
arm A few fixes for irqchip drivers: 2021-05-23 06:28:20 -10:00
arm64 ARM: SoC fixes for 5.13 2021-05-20 14:46:26 -10:00
csky arch/csky patches for 5.13-rc1 2021-05-03 12:58:31 -07:00
h8300 arch: rearrange headers inclusion order in asm/bitops for m68k, sh and h8300 2021-05-06 19:24:11 -07:00
hexagon Merge branch 'akpm' (patches from Andrew) 2021-05-07 00:34:51 -07:00
ia64 quota: Disable quotactl_path syscall 2021-05-17 14:39:56 +02:00
m68k Merge branch 'for-v5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2021-05-21 06:12:52 -10:00
microblaze quota: Disable quotactl_path syscall 2021-05-17 14:39:56 +02:00
mips quota: Disable quotactl_path syscall 2021-05-17 14:39:56 +02:00
nds32 tracing updates for 5.13 2021-05-03 11:19:54 -07:00
nios2 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-05-02 09:14:01 -07:00
openrisc OpenRISC fixes for 5.13 2021-05-21 06:06:19 -10:00
parisc quota: Disable quotactl_path syscall 2021-05-17 14:39:56 +02:00
powerpc powerpc fixes for 5.13 #4 2021-05-23 06:07:33 -10:00
riscv riscv: remove unused handle_exception symbol 2021-05-06 09:40:16 -07:00
s390 quota: Disable quotactl_path syscall 2021-05-17 14:39:56 +02:00
sh \n 2021-05-20 06:20:15 -10:00
sparc quota: Disable quotactl_path syscall 2021-05-17 14:39:56 +02:00
um Merge branch 'akpm' (patches from Andrew) 2021-05-07 00:34:51 -07:00
x86 x86/apic: Mark _all_ legacy interrupts when IO/APIC is missing 2021-05-29 11:41:14 +02:00
xtensa quota: Disable quotactl_path syscall 2021-05-17 14:39:56 +02:00
.gitignore .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
Kconfig Add Landlock, a new LSM from Mickaël Salaün <mic@linux.microsoft.com> 2021-05-01 18:50:44 -07:00