arm64: entry.S: Add ventry overflow sanity checks

commit 4330e2c5c04c27bebf89d34e0bc14e6943413067 upstream.

Subsequent patches add even more code to the ventry slots.
Ensure kernels that overflow a ventry slot don't get built.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
James Morse 2022-03-15 18:23:58 +00:00 committed by Greg Kroah-Hartman
parent 503fdc244a
commit 8aa1257128

View File

@ -59,6 +59,7 @@
.macro kernel_ventry, el, label, regsize = 64
.align 7
.Lventry_start\@:
#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
alternative_if ARM64_UNMAP_KERNEL_AT_EL0
.if \el == 0
@ -116,6 +117,7 @@ alternative_else_nop_endif
mrs x0, tpidrro_el0
#endif
b el\()\el\()_\label
.org .Lventry_start\@ + 128 // Did we overflow the ventry slot?
.endm
.macro tramp_alias, dst, sym
@ -1080,6 +1082,7 @@ alternative_else_nop_endif
add x30, x30, #(1b - tramp_vectors)
isb
ret
.org 1b + 128 // Did we overflow the ventry slot?
.endm
.macro tramp_exit, regsize = 64