x86/mce: Change to not send SIGBUS error during copy from user

mainline inclusion
from mainline-v5.16-rc1
commit a6e3cf70
category: bugfix
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I5HAC1


CVE: NA

Intel-SIG: commit a6e3cf70 x86/mce: Change to not send SIGBUS
error during copy from user.
Backport for MCA recovery enhance and bug fix.

--------------------------------

Sending a SIGBUS for a copy from user is not the correct semantic.
System calls should return -EFAULT (or a short count for write(2)).

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210818002942.1607544-3-tony.luck@intel.com


Signed-off-by: Youquan Song <youquan.song@intel.com>