mainline inclusion
from mainline-v5.12-rc1
commit 5ead723a
category: feature
bugzilla: 181005 https://gitee.com/openeuler/kernel/issues/I4EUY7

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5ead723a20e0447bc7db33dc3070b420e5f80aa6

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

If the no_hash_pointers command line parameter is set, then
printk("%p") will print pointers as unhashed, which is useful for
debugging purposes.  This change applies to any function that uses
vsprintf, such as print_hex_dump() and seq_buf_printf().

A large warning message is displayed if this option is enabled.
Unhashed pointers expose kernel addresses, which can be a security
risk.

Also update test_printf to skip the hashed pointer tests if the
command-line option is set.
Signed-off-by: NTimur Tabi <timur@kernel.org>
Acked-by: NPetr Mladek <pmladek@suse.com>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Acked-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Acked-by: NMarco Elver <elver@google.com>
Signed-off-by: NPetr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210214161348.369023-4-timur@kernel.orgSigned-off-by: NPeng Liu <liupeng256@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>