[xen stable-4.19] Arm64: adjust __irq_to_desc() to fix build with gcc14

[patchbot@xxxxxxx]

commit ee826bc490d6036ed9b637ada014a2d59d151f79
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Tue Sep 24 14:40:34 2024 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Tue Sep 24 14:40:34 2024 +0200

    Arm64: adjust __irq_to_desc() to fix build with gcc14
    
    With the original code I observe
    
    In function â??__irq_to_descâ??,
        inlined from â??route_irq_to_guestâ?? at arch/arm/irq.c:465:12:
    arch/arm/irq.c:54:16: error: array subscript -2 is below array bounds of 
â??irq_desc_t[32]â?? {aka â??struct irq_desc[32]â??} [-Werror=array-bounds=]
       54 |         return &this_cpu(local_irq_desc)[irq];
          |                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    
    which looks pretty bogus: How in the world does the compiler arrive at
    -2 when compiling route_irq_to_guest()? Yet independent of that the
    function's parameter wants to be of unsigned type anyway, as shown by
    a vast majority of callers (others use plain int when they really mean
    non-negative quantities). With that adjustment the code compiles fine
    again.
    
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Acked-by: Michal Orzel <michal.orzel@xxxxxxx>
    master commit: 99f942f3d410059dc223ee0a908827e928ef3592
    master date: 2024-08-29 10:03:53 +0200
---
 xen/arch/arm/include/asm/irq.h | 2 +-
 xen/arch/arm/irq.c             | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/xen/arch/arm/include/asm/irq.h b/xen/arch/arm/include/asm/irq.h
index ec437add09..88e060bf29 100644
--- a/xen/arch/arm/include/asm/irq.h
+++ b/xen/arch/arm/include/asm/irq.h
@@ -56,7 +56,7 @@ extern const unsigned int nr_irqs;
 struct irq_desc;
 struct irqaction;
 
-struct irq_desc *__irq_to_desc(int irq);
+struct irq_desc *__irq_to_desc(unsigned int irq);
 
 #define irq_to_desc(irq)    __irq_to_desc(irq)
 
diff --git a/xen/arch/arm/irq.c b/xen/arch/arm/irq.c
index 6b89f64fd1..b9757d7ad3 100644
--- a/xen/arch/arm/irq.c
+++ b/xen/arch/arm/irq.c
@@ -48,7 +48,7 @@ void irq_end_none(struct irq_desc *irq)
 static irq_desc_t irq_desc[NR_IRQS];
 static DEFINE_PER_CPU(irq_desc_t[NR_LOCAL_IRQS], local_irq_desc);
 
-struct irq_desc *__irq_to_desc(int irq)
+struct irq_desc *__irq_to_desc(unsigned int irq)
 {
     if ( irq < NR_LOCAL_IRQS )
         return &this_cpu(local_irq_desc)[irq];
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.19