arm64: entry.S: Add ventry overflow sanity checks

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>
This commit is contained in:
James Morse 2021-11-17 15:15:26 +00:00
parent dfd42facf1
commit 4330e2c5c0

View file

@ -37,6 +37,7 @@
.macro kernel_ventry, el:req, ht:req, regsize:req, label:req
.align 7
.Lventry_start\@:
#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
.if \el == 0
alternative_if ARM64_UNMAP_KERNEL_AT_EL0
@ -95,6 +96,7 @@ alternative_else_nop_endif
mrs x0, tpidrro_el0
#endif
b el\el\ht\()_\regsize\()_\label
.org .Lventry_start\@ + 128 // Did we overflow the ventry slot?
.endm
.macro tramp_alias, dst, sym
@ -662,6 +664,7 @@ 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