[xen master] x86/PV: adjust APPEND_CALL() to comply to Misra rule 18.2

[patchbot@xxxxxxx]

commit 6c98c5368f846d7f35f63b434180e4d48fb87f56
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Mon Oct 12 09:39:13 2026 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Oct 12 09:39:13 2026 +0200

    x86/PV: adjust APPEND_CALL() to comply to Misra rule 18.2
    
    While casting to pointer types may be more natural there, the subtraction
    then ends up violating "Subtraction between pointers shall only be applied
    to pointers that address elements of the same array". Use long arithmetic
    instead.
    
    No functional change intended.
    
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Dmytro Prokopchuk <dmytro_prokopchuk1@xxxxxxxx>
---
 xen/arch/x86/pv/emul-priv-op.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/xen/arch/x86/pv/emul-priv-op.c b/xen/arch/x86/pv/emul-priv-op.c
index fd9b533e57..9d41f787f2 100644
--- a/xen/arch/x86/pv/emul-priv-op.c
+++ b/xen/arch/x86/pv/emul-priv-op.c
@@ -92,7 +92,8 @@ static io_emul_stub_t *io_emul_stub_setup(struct priv_op_ctxt 
*ctxt, u8 opcode,
 #define APPEND_BUFF(b) ({ memcpy(p, b, sizeof(b)); p += sizeof(b); })
 #define APPEND_CALL(f)                                                  \
     ({                                                                  \
-        long disp = (void *)(f) - (stub_va + (p - ctxt->io_emul_stub) + 5); \
+        long disp = (long)(f) -                                         \
+                    ((long)stub_va + (p - ctxt->io_emul_stub) + 5);     \
         BUG_ON((int32_t)disp != disp);                                  \
         *p++ = 0xe8;                                                    \
         *(int32_t *)p = disp; p += 4;                                   \
--
generated by git-patchbot for /home/xen/git/xen.git#master