[xen master] xen/arm: Restrict zeroeth_table_offset for ARM_64

[patchbot@xxxxxxx]

commit 7c72147baa221cb49da80498bb0360c4d24a759f
Author:     Ayan Kumar Halder <ayan.kumar.halder@xxxxxxx>
AuthorDate: Fri Jun 2 13:07:53 2023 +0100
Commit:     Julien Grall <jgrall@xxxxxxxxxx>
CommitDate: Fri Jun 16 21:36:35 2023 +0100

    xen/arm: Restrict zeroeth_table_offset for ARM_64
    
    When 32 bit physical addresses are used (ie PHYS_ADDR_T_32=y),
    "va >> ZEROETH_SHIFT" causes an overflow.
    Also, there is no zeroeth level page table on Arm32.
    
    Also took the opportunity to clean up dump_pt_walk(). One could use
    DECLARE_OFFSETS() macro instead of declaring an array of page table
    offsets.
    
    Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@xxxxxxx>
    Reviewed-by: Michal Orzel <michal.orzel@xxxxxxx>
    Acked-by: Julien Grall <jgrall@xxxxxxxxxx>
---
 xen/arch/arm/include/asm/lpae.h | 4 ++++
 xen/arch/arm/mm.c               | 7 +------
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/xen/arch/arm/include/asm/lpae.h b/xen/arch/arm/include/asm/lpae.h
index 3fdd5d0de2..7d2f6fd1bd 100644
--- a/xen/arch/arm/include/asm/lpae.h
+++ b/xen/arch/arm/include/asm/lpae.h
@@ -259,7 +259,11 @@ lpae_t mfn_to_xen_entry(mfn_t mfn, unsigned int attr);
 #define first_table_offset(va)  TABLE_OFFSET(first_linear_offset(va))
 #define second_table_offset(va) TABLE_OFFSET(second_linear_offset(va))
 #define third_table_offset(va)  TABLE_OFFSET(third_linear_offset(va))
+#ifdef CONFIG_PHYS_ADDR_T_32
+#define zeroeth_table_offset(va)  0
+#else
 #define zeroeth_table_offset(va)  TABLE_OFFSET(zeroeth_linear_offset(va))
+#endif
 
 /*
  * Macros to define page-tables:
diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index 5ef5fd8c49..e460249736 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -233,12 +233,7 @@ void dump_pt_walk(paddr_t ttbr, paddr_t addr,
 {
     static const char *level_strs[4] = { "0TH", "1ST", "2ND", "3RD" };
     const mfn_t root_mfn = maddr_to_mfn(ttbr);
-    const unsigned int offsets[4] = {
-        zeroeth_table_offset(addr),
-        first_table_offset(addr),
-        second_table_offset(addr),
-        third_table_offset(addr)
-    };
+    DECLARE_OFFSETS(offsets, addr);
     lpae_t pte, *mapping;
     unsigned int level, root_table;
 
--
generated by git-patchbot for /home/xen/git/xen.git#master