@@ -701,18 +701,45 @@ static struct sys_reg_desc invariant_sys_regs[] = {
NULL, get_ctr_el0 },
};
-static int reg_from_user(void *val, const void __user *uaddr, u64 id)
+static int reg_from_user(u64 *val, const void __user *uaddr, u64 id)
{
- /* This Just Works because we are little endian. */
- if (copy_from_user(val, uaddr, KVM_REG_SIZE(id)) != 0)
+ unsigned long regsize = KVM_REG_SIZE(id);
+ union {
+ u32 word;
+ u64 dword;
+ } tmp = {0};
+
+ if (copy_from_user(&tmp, uaddr, regsize) != 0)
return -EFAULT;
+ switch (regsize) {
+ case 4:
+ *val = tmp.word;
+ break;
+ case 8:
+ *val = tmp.dword;
+ break;
+ }
return 0;
}
-static int reg_to_user(void __user *uaddr, const void *val, u64 id)
+static int reg_to_user(void __user *uaddr, const u64 *val, u64 id)
{
- /* This Just Works because we are little endian. */
- if (copy_to_user(uaddr, val, KVM_REG_SIZE(id)) != 0)
+ unsigned long regsize = KVM_REG_SIZE(id);
+ union {
+ u32 word;
+ u64 dword;
+ } tmp;
+
+ switch (regsize) {
+ case 4:
+ tmp.word = *val;
+ break;
+ case 8:
+ tmp.dword = *val;
+ break;
+ }
+
+ if (copy_to_user(uaddr, &tmp, regsize) != 0)
return -EFAULT;
return 0;
}
This patch fixes issue of reading and writing V8 sys registers in BE case. It is similar to V7 "ARM: kvm one_reg coproc set and get BE fixes" patch. It changes reg_from_user and reg_to_user functions to have strong typed 'u64 *val' argument. And it uses endian angnostic way to pick up righ word from '*val' in case when register size is 4 bytes. Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org> --- arch/arm64/kvm/sys_regs.c | 39 +++++++++++++++++++++++++++++++++------ 1 file changed, 33 insertions(+), 6 deletions(-)