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efi: Prevent GICv3 WARN() by mapping the memreserve table before first use

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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: 63eb322d89 ("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>
This commit is contained in:
Ard Biesheuvel 2018-11-23 22:51:32 +01:00 committed by Ingo Molnar
parent 2e6e902d18
commit 976b489120
1 changed files with 26 additions and 10 deletions
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36
drivers/firmware/efi/efi.c
View File

@ -969,13 +969,33 @@ bool efi_is_table_address(unsigned long phys_addr)
static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock);
static struct linux_efi_memreserve *efi_memreserve_root __ro_after_init; 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; struct linux_efi_memreserve *rsv;
int rc;
if (!efi_memreserve_root) if (efi_memreserve_root == (void *)ULONG_MAX)
return -ENODEV; return -ENODEV;
if (!efi_memreserve_root) {
rc = efi_memreserve_map_root();
if (rc)
return rc;
}
rsv = kmalloc(sizeof(*rsv), GFP_ATOMIC); rsv = kmalloc(sizeof(*rsv), GFP_ATOMIC);
if (!rsv) if (!rsv)
return -ENOMEM; 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) static int __init efi_memreserve_root_init(void)
{ {
if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR) if (efi_memreserve_root)
return -ENODEV; return 0;
if (efi_memreserve_map_root())
efi_memreserve_root = memremap(efi.mem_reserve, efi_memreserve_root = (void *)ULONG_MAX;
sizeof(*efi_memreserve_root),
MEMREMAP_WB);
if (!efi_memreserve_root)
return -ENOMEM;
return 0; return 0;
} }
early_initcall(efi_memreserve_root_init); early_initcall(efi_memreserve_root_init);