So far, we only reserve a single instruction in the BPI template in
order to branch to the vectors. As we're going to stuff a few more
instructions there, let's reserve a total of 5 instructions, which
we're going to patch later on as required.

We also introduce a small refactor of the vectors themselves, so that
we stop carrying the target branch around.

Signed-off-by: Marc Zyngier <[email protected]>
---
 arch/arm64/kernel/bpi.S | 39 +++++++++++++++------------------------
 1 file changed, 15 insertions(+), 24 deletions(-)

diff --git a/arch/arm64/kernel/bpi.S b/arch/arm64/kernel/bpi.S
index 447188e2a664..ce1cfe3b24e6 100644
--- a/arch/arm64/kernel/bpi.S
+++ b/arch/arm64/kernel/bpi.S
@@ -19,33 +19,24 @@
 #include <linux/linkage.h>
 #include <linux/arm-smccc.h>
 
-.macro ventry target
-       .rept 31
+.macro hyp_ventry
+       .align 7
+1:     .rept 27
        nop
        .endr
-       b       \target
+       b       __kvm_hyp_vector + (1b - 0b)
+       nop
+       nop
+       nop
+       nop
 .endm
 
-.macro vectors target
-       ventry \target + 0x000
-       ventry \target + 0x080
-       ventry \target + 0x100
-       ventry \target + 0x180
-
-       ventry \target + 0x200
-       ventry \target + 0x280
-       ventry \target + 0x300
-       ventry \target + 0x380
-
-       ventry \target + 0x400
-       ventry \target + 0x480
-       ventry \target + 0x500
-       ventry \target + 0x580
-
-       ventry \target + 0x600
-       ventry \target + 0x680
-       ventry \target + 0x700
-       ventry \target + 0x780
+.macro generate_vectors
+0:
+       .rept 16
+       hyp_ventry
+       .endr
+       .org 0b + SZ_2K         // Safety measure
 .endm
 
 
@@ -55,7 +46,7 @@
        .align  11
 ENTRY(__bp_harden_hyp_vecs_start)
        .rept 4
-       vectors __kvm_hyp_vector
+       generate_vectors
        .endr
 ENTRY(__bp_harden_hyp_vecs_end)
 
-- 
2.14.2

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