efi/arm: Defer persistent reservations until after paging_init()

The new memory EFI reservation feature we introduced to allow memory
reservations to persist across kexec may trigger an unbounded number
of calls to memblock_reserve(). The memblock subsystem can deal with
this fine, but not before memblock resizing is enabled, which we can
only do after paging_init(), when the memory we reallocate the array
into is actually mapped.

So break out the memreserve table processing into a separate routine
and call it after paging_init() on arm64. On ARM, because of limited
reviewing bandwidth of the maintainer, we cannot currently fix this,
so instead, disable the EFI persistent memreserve entirely on ARM so
we can fix it later.

Tested-by: Marc Zyngier <marc.zyngier@arm.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
Link: http://lkml.kernel.org/r/20181114175544.12860-5-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ard Biesheuvel 2018-11-14 09:55:43 -08:00 committed by Ingo Molnar
parent 72a58a63a1
commit eff8962888
4 changed files with 15 additions and 0 deletions

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@ -313,6 +313,7 @@ void __init setup_arch(char **cmdline_p)
arm64_memblock_init();
paging_init();
efi_apply_persistent_mem_reservations();
acpi_table_upgrade();

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@ -592,7 +592,11 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,
early_memunmap(tbl, sizeof(*tbl));
}
return 0;
}
int __init efi_apply_persistent_mem_reservations(void)
{
if (efi.mem_reserve != EFI_INVALID_TABLE_ADDR) {
unsigned long prsv = efi.mem_reserve;

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@ -75,6 +75,9 @@ void install_memreserve_table(efi_system_table_t *sys_table_arg)
efi_guid_t memreserve_table_guid = LINUX_EFI_MEMRESERVE_TABLE_GUID;
efi_status_t status;
if (IS_ENABLED(CONFIG_ARM))
return;
status = efi_call_early(allocate_pool, EFI_LOADER_DATA, sizeof(*rsv),
(void **)&rsv);
if (status != EFI_SUCCESS) {

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@ -1167,6 +1167,8 @@ static inline bool efi_enabled(int feature)
extern void efi_reboot(enum reboot_mode reboot_mode, const char *__unused);
extern bool efi_is_table_address(unsigned long phys_addr);
extern int efi_apply_persistent_mem_reservations(void);
#else
static inline bool efi_enabled(int feature)
{
@ -1185,6 +1187,11 @@ static inline bool efi_is_table_address(unsigned long phys_addr)
{
return false;
}
static inline int efi_apply_persistent_mem_reservations(void)
{
return 0;
}
#endif
extern int efi_status_to_err(efi_status_t status);