Jason A. Donenfeld 7690be1adf timekeeping: Add raw clock fallback for random_get_entropy() ... commit 1366992e16 upstream. The addition of random_get_entropy_fallback() provides access to whichever time source has the highest frequency, which is useful for gathering entropy on platforms without available cycle counters. It's not necessarily as good as being able to quickly access a cycle counter that the CPU has, but it's still something, even when it falls back to being jiffies-based. In the event that a given arch does not define get_cycles(), falling back to the get_cycles() default implementation that returns 0 is really not the best we can do. Instead, at least calling random_get_entropy_fallback() would be preferable, because that always needs to return _something_, even falling back to jiffies eventually. It's not as though random_get_entropy_fallback() is super high precision or guaranteed to be entropic, but basically anything that's not zero all the time is better than returning zero all the time. Finally, since random_get_entropy_fallback() is used during extremely early boot when randomizing freelists in mm_init(), it can be called before timekeeping has been initialized. In that case there really is nothing we can do; jiffies hasn't even started ticking yet. So just give up and return 0. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-05-30 09:33:41 +02:00
..
acpi	ACPICA: actypes.h: Expand the ACPI_ACCESS_ definitions	2022-01-27 10:54:18 +01:00
asm-generic	tlb: hugetlb: Add more sizes to tlb_remove_huge_tlb_entry	2022-04-20 09:23:22 +02:00
clocksource	clocksource/drivers/timer-ti-dm: Save and restore timer TIOCP_CFG	2021-07-14 16:56:12 +02:00
crypto	random: replace custom notifier chain with standard one	2022-05-30 09:33:38 +02:00
drm	drm: protect drm_master pointers in drm_lease.c	2021-09-18 13:40:19 +02:00
dt-bindings	clk: imx8mq: remove SYS PLL 1/2 clock gates	2021-07-14 16:56:20 +02:00
keys	certs: Add EFI_CERT_X509_GUID support for dbx entries	2021-06-30 08:47:30 -04:00
kunit	kunit: fix display of failed expectations for strings	2020-11-10 13:45:15 -07:00
kvm	ARM:	2020-10-23 11:17:56 -07:00
linux	timekeeping: Add raw clock fallback for random_get_entropy()	2022-05-30 09:33:41 +02:00
math-emu
media	media: subdev: disallow ioctl for saa6588/davinci	2021-07-19 09:45:02 +02:00
memory	memory: renesas-rpc-if: Fix HF/OSPI data transfer in Manual Mode	2022-05-09 09:05:02 +02:00
misc
net	secure_seq: use the 64 bits of the siphash for port offset calculation	2022-05-30 09:33:23 +02:00
pcmcia
ras	mm,hwpoison: introduce MF_MSG_UNSPLIT_THP	2020-10-16 11:11:17 -07:00
rdma	RDMA/netlink: Add __maybe_unused to static inline in C file	2021-11-26 10:39:21 +01:00
scsi	scsi: iscsi: Fix conn cleanup and stop race during iscsid restart	2022-04-20 09:23:17 +02:00
soc	firmware: raspberrypi: Keep count of all consumers	2021-09-15 09:50:41 +02:00
sound	ALSA: pcm: Fix potential AB/BA lock with buffer_mutex and mmap_lock	2022-04-08 14:39:53 +02:00
target	scsi: target: Fix ordered tag handling	2021-11-26 10:39:11 +01:00
trace	random: remove unused tracepoints	2022-05-30 09:33:34 +02:00
uapi	include/uapi/linux/xfrm.h: Fix XFRM_MSG_MAPPING ABI breakage	2022-05-25 09:18:02 +02:00
vdso
video	gpu: ipu-v3: remove unused functions	2020-10-26 10:42:38 +01:00
xen	xen/gnttab: fix gnttab_end_foreign_access() without page specified	2022-03-11 12:11:54 +01:00