Re: [PATCH v12 15/22] selftests/vm: powerpc implementation to check support for pkey
From: Dave Hansen <hidden>
Date: 2018-03-16 22:26:19
Also in:
linux-arch, linux-doc, linux-kselftest, linux-mm, lkml
On 02/21/2018 05:55 PM, Ram Pai wrote:
#define PAGE_SIZE (0x1UL << 16)
-static inline int cpu_has_pku(void)
+static inline bool is_pkey_supported(void)
{
- return 1;
+ /*
+ * No simple way to determine this.
+ * lets try allocating a key and see if it succeeds.
+ */
+ int ret = sys_pkey_alloc(0, 0);
+
+ if (ret > 0) {
+ sys_pkey_free(ret);
+ return true;
+ }
+ return false;
}The point of doing this was to have a test for the CPU that way separate from the syscalls. Can you leave cpu_has_pkeys() in place?