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author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2018-11-24 00:51:32 +0300 |
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committer | Ingo Molnar <mingo@kernel.org> | 2018-11-27 15:50:20 +0300 |
commit | 976b489120cdab2b1b3a41ffa14661db43d58190 (patch) | |
tree | 5a6de1fcdcdbe44bca84a1ec22f91370eed5fad0 /drivers | |
parent | 2e6e902d185027f8e3cb8b7305238f7e35d6a436 (diff) | |
download | linux-976b489120cdab2b1b3a41ffa14661db43d58190.tar.xz |
efi: Prevent GICv3 WARN() by mapping the memreserve table before first use
Mapping the MEMRESERVE EFI configuration table from an early initcall
is too late: the GICv3 ITS code that creates persistent reservations
for the boot CPU's LPI tables is invoked from init_IRQ(), which runs
much earlier than the handling of the initcalls. This results in a
WARN() splat because the LPI tables cannot be reserved persistently,
which will result in silent memory corruption after a kexec reboot.
So instead, invoke the initialization performed by the initcall from
efi_mem_reserve_persistent() itself as well, but keep the initcall so
that the init is guaranteed to have been called before SMP boot.
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Jan Glauber <jglauber@cavium.com>
Tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 63eb322d89c8 ("efi: Permit calling efi_mem_reserve_persistent() ...")
Link: http://lkml.kernel.org/r/20181123215132.7951-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/firmware/efi/efi.c | 36 |
1 files changed, 26 insertions, 10 deletions
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index fad7c62cfc0e..415849bab233 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -969,13 +969,33 @@ bool efi_is_table_address(unsigned long phys_addr) static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; -int efi_mem_reserve_persistent(phys_addr_t addr, u64 size) +static int __init efi_memreserve_map_root(void) +{ + if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR) + return -ENODEV; + + efi_memreserve_root = memremap(efi.mem_reserve, + sizeof(*efi_memreserve_root), + MEMREMAP_WB); + if (WARN_ON_ONCE(!efi_memreserve_root)) + return -ENOMEM; + return 0; +} + +int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) { struct linux_efi_memreserve *rsv; + int rc; - if (!efi_memreserve_root) + if (efi_memreserve_root == (void *)ULONG_MAX) return -ENODEV; + if (!efi_memreserve_root) { + rc = efi_memreserve_map_root(); + if (rc) + return rc; + } + rsv = kmalloc(sizeof(*rsv), GFP_ATOMIC); if (!rsv) return -ENOMEM; @@ -993,14 +1013,10 @@ int efi_mem_reserve_persistent(phys_addr_t addr, u64 size) static int __init efi_memreserve_root_init(void) { - if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR) - return -ENODEV; - - efi_memreserve_root = memremap(efi.mem_reserve, - sizeof(*efi_memreserve_root), - MEMREMAP_WB); - if (!efi_memreserve_root) - return -ENOMEM; + if (efi_memreserve_root) + return 0; + if (efi_memreserve_map_root()) + efi_memreserve_root = (void *)ULONG_MAX; return 0; } early_initcall(efi_memreserve_root_init); |