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author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2017-03-01 19:05:54 (GMT) |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-03-18 11:14:29 (GMT) |
commit | 56d91e106b13f81fea9a6571240ab89eba6d9fe8 (patch) | |
tree | d1f0cdfa325adbc15f7e61202cbf9ff0f61846a7 /drivers/firmware/efi | |
parent | ee6f7ee1e4cdb0098fee4593ddf11ca6028abef2 (diff) | |
download | linux-56d91e106b13f81fea9a6571240ab89eba6d9fe8.tar.xz |
efi/arm: Fix boot crash with CONFIG_CPUMASK_OFFSTACK=y
commit d1eb98143c56f24fef125f5bbed49ae0b52fb7d6 upstream.
On ARM and arm64, we use a dedicated mm_struct to map the UEFI
Runtime Services regions, which allows us to map those regions
on demand, and in a way that is guaranteed to be compatible
with incoming kernels across kexec.
As it turns out, we don't fully initialize the mm_struct in the
same way as process mm_structs are initialized on fork(), which
results in the following crash on ARM if CONFIG_CPUMASK_OFFSTACK=y
is enabled:
...
EFI Variables Facility v0.08 2004-May-17
Unable to handle kernel NULL pointer dereference at virtual address 00000000
[...]
Process swapper/0 (pid: 1)
...
__memzero()
check_and_switch_context()
virt_efi_get_next_variable()
efivar_init()
efivars_sysfs_init()
do_one_initcall()
...
This is due to a missing call to mm_init_cpumask(), so add it.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1488395154-29786-1-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/firmware/efi')
-rw-r--r-- | drivers/firmware/efi/arm-runtime.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c index 7c75a8d..6bdf39e 100644 --- a/drivers/firmware/efi/arm-runtime.c +++ b/drivers/firmware/efi/arm-runtime.c @@ -65,6 +65,7 @@ static bool __init efi_virtmap_init(void) bool systab_found; efi_mm.pgd = pgd_alloc(&efi_mm); + mm_init_cpumask(&efi_mm); init_new_context(NULL, &efi_mm); systab_found = false; |