From: Arnd Bergmann <arnd@xxxxxxxx>
gcc gets confused by the comparison of a pointer to an integer listeral,
with the assumption that this is an offset from a NULL pointer and that
dereferencing it is invalid:
In file included from arch/x86/boot/compressed/misc.c:18:
In function ‘parse_elf’,
inlined from ‘extract_kernel’ at arch/x86/boot/compressed/misc.c:442:2:
arch/x86/boot/compressed/../string.h:15:23: error: ‘__builtin_memcpy’ reading 64 bytes from a region of size 0 [-Werror=stringop-overread]
15 | #define memcpy(d,s,l) __builtin_memcpy(d,s,l)
| ^~~~~~~~~~~~~~~~~~~~~~~
arch/x86/boot/compressed/misc.c:283:9: note: in expansion of macro ‘memcpy’
283 | memcpy(&ehdr, output, sizeof(ehdr));
| ^~~~~~
I could not find any good workaround for this, but as this is only
a warning for a failure during early boot, removing the line entirely
works around the warning.
This should probably get addressed in gcc instead, before 11.1 gets
released.
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/x86/boot/compressed/misc.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 3a214cc3239f..9ada64e66cb7 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -430,8 +430,6 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
error("Destination address too large");
#endif
#ifndef CONFIG_RELOCATABLE
- if ((unsigned long)output != LOAD_PHYSICAL_ADDR)
- error("Destination address does not match LOAD_PHYSICAL_ADDR");
if (virt_addr != LOAD_PHYSICAL_ADDR)
error("Destination virtual address changed when not relocatable");
#endif
--
2.29.2
