[PATCH 14/18] Allow efi_free() to be called with size of 0, and do nothing in that case.

From: Roy Franz
Date: Sun Sep 22 2013 - 18:47:13 EST


Make efi_free() safely callable with size of 0, similar to free() being
callable with NULL pointers.
Remove size checks that this makes redundant. This also avoids some
size checks in the ARM EFI stub code that will be added as well.

Signed-off-by: Roy Franz <roy.franz@xxxxxxxxxx>
---
arch/x86/boot/compressed/eboot.c | 3 +--
drivers/firmware/efi/efi-stub-helper.c | 3 +++
2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 05f11c7..8b86772 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -505,8 +505,7 @@ struct boot_params *make_boot_params(void *handle, efi_system_table_t *_table)

return boot_params;
fail2:
- if (options_size)
- efi_free(sys_table, options_size, hdr->cmd_line_ptr);
+ efi_free(sys_table, options_size, hdr->cmd_line_ptr);
fail:
efi_free(sys_table, 0x4000, (unsigned long)boot_params);
return NULL;
diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/efi-stub-helper.c
index b0b2f15..73cf86b 100644
--- a/drivers/firmware/efi/efi-stub-helper.c
+++ b/drivers/firmware/efi/efi-stub-helper.c
@@ -253,6 +253,9 @@ static void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
{
unsigned long nr_pages;

+ if (!size)
+ return;
+
nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
efi_call_phys2(sys_table_arg->boottime->free_pages, addr, nr_pages);
}
--
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/