diff options
| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2017-03-01 22:05:54 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-03-02 10:11:19 +0300 |
| commit | d1eb98143c56f24fef125f5bbed49ae0b52fb7d6 (patch) | |
| tree | a16cf1a9365bb65fd68d7e7f40903fb368d2005e /drivers/firmware | |
| parent | 52e51f16407b7b34e26affb500a21e250d9fce0b (diff) | |
| download | linux-d1eb98143c56f24fef125f5bbed49ae0b52fb7d6.tar.xz | |
efi/arm: Fix boot crash with CONFIG_CPUMASK_OFFSTACK=y
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: <stable@vger.kernel.org> # v4.5+
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>
Diffstat (limited to 'drivers/firmware')
| -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 349dc3e1e52e..974c5a31a005 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; |