On 6 November 2018 at 12:37, Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> wrote:
> 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 function
> and call if after paging_init() on both arm64 and ARM.
>
> Cc: Russell King <linux@xxxxxxxxxxxxxxx>
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Russell,
If you are ok with this patch, may I have your ack please? I would
like to send it out before the end of the week.
Thanks,
> ---
> arch/arm/kernel/setup.c | 1 +
> arch/arm64/kernel/setup.c | 1 +
> drivers/firmware/efi/efi.c | 8 ++++++--
> include/linux/efi.h | 7 +++++++
> 4 files changed, 15 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
> index ac7e08886863..e99f12eaf390 100644
> --- a/arch/arm/kernel/setup.c
> +++ b/arch/arm/kernel/setup.c
> @@ -1117,6 +1117,7 @@ void __init setup_arch(char **cmdline_p)
> early_ioremap_reset();
>
> paging_init(mdesc);
> + efi_apply_persistent_mem_reservations();
> request_standard_resources(mdesc);
>
> if (mdesc->restart)
> diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
> index 953e316521fc..f4fc1e0544b7 100644
> --- a/arch/arm64/kernel/setup.c
> +++ b/arch/arm64/kernel/setup.c
> @@ -313,6 +313,7 @@ void __init setup_arch(char **cmdline_p)
> arm64_memblock_init();
>
> paging_init();
> + efi_apply_persistent_mem_reservations();
>
> acpi_table_upgrade();
>
> diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
> index 249eb70691b0..55e4ea20bdc3 100644
> --- a/drivers/firmware/efi/efi.c
> +++ b/drivers/firmware/efi/efi.c
> @@ -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;
>
> @@ -602,7 +606,7 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,
> /* reserve the entry itself */
> memblock_reserve(prsv, sizeof(*rsv));
>
> - rsv = early_memremap(prsv, sizeof(*rsv));
> + rsv = memremap(prsv, sizeof(*rsv), MEMREMAP_WB);
> if (rsv == NULL) {
> pr_err("Could not map UEFI memreserve entry!\n");
> return -ENOMEM;
> @@ -612,7 +616,7 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,
> memblock_reserve(rsv->base, rsv->size);
>
> prsv = rsv->next;
> - early_memunmap(rsv, sizeof(*rsv));
> + memunmap(rsv);
> }
> }
>
> diff --git a/include/linux/efi.h b/include/linux/efi.h
> index 845174e113ce..100ce4a4aff6 100644
> --- a/include/linux/efi.h
> +++ b/include/linux/efi.h
> @@ -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);
> --
> 2.19.1
>
