[PATCH] linux-user: fix handling of cpu mask in riscv_hwprobe syscall

Andreas Schwab posted 1 patch 5 hours ago
linux-user/syscall.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
[PATCH] linux-user: fix handling of cpu mask in riscv_hwprobe syscall
Posted by Andreas Schwab 5 hours ago
The third argument of the riscv_hwprobe syscall contains the size of the
cpu mask in bytes, not bits.

Signed-off-by: Andreas Schwab <schwab@suse.de>
---
 linux-user/syscall.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index a22a5df8cc..4cc1a31d0d 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -9120,16 +9120,16 @@ static void risc_hwprobe_fill_pairs(CPURISCVState *env,
 
 static int cpu_set_valid(abi_long arg3, abi_long arg4)
 {
-    int ret, i, tmp;
+    int ret, i;
     size_t host_mask_size, target_mask_size;
     unsigned long *host_mask;
 
     /*
      * cpu_set_t represent CPU masks as bit masks of type unsigned long *.
-     * arg3 contains the cpu count.
+     * arg3 contains the size of the cpu mask.
      */
-    tmp = (8 * sizeof(abi_ulong));
-    target_mask_size = ((arg3 + tmp - 1) / tmp) * sizeof(abi_ulong);
+    target_mask_size = (arg3 + (sizeof(abi_ulong) - 1)) &
+                       ~(sizeof(abi_ulong) - 1);
     host_mask_size = (target_mask_size + (sizeof(*host_mask) - 1)) &
                      ~(sizeof(*host_mask) - 1);
 
-- 
2.48.1


-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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