* [PATCH] afs: correctly use 64-bit time for UUID
@ 2017-01-11 13:44 Arnd Bergmann
2017-01-11 13:51 ` David Howells
0 siblings, 1 reply; 10+ messages in thread
From: Arnd Bergmann @ 2017-01-11 13:44 UTC (permalink / raw)
To: David Howells; +Cc: Tina Ruchandani, Arnd Bergmann, linux-afs, linux-kernel
From: Tina Ruchandani <ruchandani.tina@gmail.com>
UUID calculation uses 'struct timespec' whose seconds will overflow
in year 2038 and beyond for 32-bit systems. This patch removes the
dependency on 'struct timespec' by using ktime_get_real().
While the patch does not fix a 'bug' as such, it is part of a larger
effort to remove instances of 'struct timespec' and other data-structures
suffering from y2038 problem from the kernel.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
fs/afs/main.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/fs/afs/main.c b/fs/afs/main.c
index f8188feb03ad..59e7ef38e541 100644
--- a/fs/afs/main.c
+++ b/fs/afs/main.c
@@ -13,6 +13,7 @@
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/completion.h>
+#include <linux/ktime.h>
#include <linux/sched.h>
#include <linux/random.h>
#define CREATE_TRACE_POINTS
@@ -39,7 +40,6 @@ struct workqueue_struct *afs_wq;
*/
static int __init afs_get_client_UUID(void)
{
- struct timespec ts;
u64 uuidtime;
u16 clockseq;
int ret;
@@ -50,9 +50,7 @@ static int __init afs_get_client_UUID(void)
if (ret < 0)
return ret;
- getnstimeofday(&ts);
- uuidtime = (u64) ts.tv_sec * 1000 * 1000 * 10;
- uuidtime += ts.tv_nsec / 100;
+ uuidtime = ktime_divns(ktime_get_real(), 100);
uuidtime += AFS_UUID_TO_UNIX_TIME;
afs_uuid.time_low = uuidtime;
afs_uuid.time_mid = uuidtime >> 32;
--
2.9.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH] afs: correctly use 64-bit time for UUID
2017-01-11 13:44 [PATCH] afs: correctly use 64-bit time for UUID Arnd Bergmann
@ 2017-01-11 13:51 ` David Howells
2017-01-11 14:03 ` Arnd Bergmann
2017-01-11 14:47 ` David Howells
0 siblings, 2 replies; 10+ messages in thread
From: David Howells @ 2017-01-11 13:51 UTC (permalink / raw)
To: Arnd Bergmann; +Cc: dhowells, Tina Ruchandani, linux-afs, linux-kernel
Arnd Bergmann <arnd@arndb.de> wrote:
> From: Tina Ruchandani <ruchandani.tina@gmail.com>
>
> UUID calculation uses 'struct timespec' whose seconds will overflow
> in year 2038 and beyond for 32-bit systems. This patch removes the
> dependency on 'struct timespec' by using ktime_get_real().
> While the patch does not fix a 'bug' as such, it is part of a larger
> effort to remove instances of 'struct timespec' and other data-structures
> suffering from y2038 problem from the kernel.
Is it worth abstracting out in-kernel UUID generation?
David
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] afs: correctly use 64-bit time for UUID
2017-01-11 13:51 ` David Howells
@ 2017-01-11 14:03 ` Arnd Bergmann
2017-01-11 14:47 ` David Howells
1 sibling, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2017-01-11 14:03 UTC (permalink / raw)
To: David Howells; +Cc: Tina Ruchandani, linux-afs, linux-kernel
On Wednesday, January 11, 2017 1:51:32 PM CET David Howells wrote:
> Arnd Bergmann <arnd@arndb.de> wrote:
>
> > From: Tina Ruchandani <ruchandani.tina@gmail.com>
> >
> > UUID calculation uses 'struct timespec' whose seconds will overflow
> > in year 2038 and beyond for 32-bit systems. This patch removes the
> > dependency on 'struct timespec' by using ktime_get_real().
> > While the patch does not fix a 'bug' as such, it is part of a larger
> > effort to remove instances of 'struct timespec' and other data-structures
> > suffering from y2038 problem from the kernel.
>
> Is it worth abstracting out in-kernel UUID generation?
Do you mean moving it out of AFS into lib/*.c? I think the 'afs_uuid'
structure is quite different from other UUID definitions, so that wouldn't
work.
Arnd
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] afs: correctly use 64-bit time for UUID
2017-01-11 13:51 ` David Howells
2017-01-11 14:03 ` Arnd Bergmann
@ 2017-01-11 14:47 ` David Howells
2017-01-11 15:55 ` Arnd Bergmann
1 sibling, 1 reply; 10+ messages in thread
From: David Howells @ 2017-01-11 14:47 UTC (permalink / raw)
To: Arnd Bergmann; +Cc: dhowells, Tina Ruchandani, linux-afs, linux-kernel
Arnd Bergmann <arnd@arndb.de> wrote:
> > Is it worth abstracting out in-kernel UUID generation?
>
> Do you mean moving it out of AFS into lib/*.c? I think the 'afs_uuid'
> structure is quite different from other UUID definitions, so that wouldn't
> work.
afs_uuid is as it is to make it easier to package into the on-wire format, but
I suspect there's no problem with using a completely random UUID instead and
divvying it up the same way.
David
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] afs: correctly use 64-bit time for UUID
2017-01-11 14:47 ` David Howells
@ 2017-01-11 15:55 ` Arnd Bergmann
2017-01-12 9:27 ` [PATCH] afs: use random UUID kbuild test robot
0 siblings, 1 reply; 10+ messages in thread
From: Arnd Bergmann @ 2017-01-11 15:55 UTC (permalink / raw)
To: David Howells; +Cc: Tina Ruchandani, linux-afs, linux-kernel
On Wednesday, January 11, 2017 2:47:20 PM CET David Howells wrote:
> Arnd Bergmann <arnd@arndb.de> wrote:
>
> > > Is it worth abstracting out in-kernel UUID generation?
> >
> > Do you mean moving it out of AFS into lib/*.c? I think the 'afs_uuid'
> > structure is quite different from other UUID definitions, so that wouldn't
> > work.
>
> afs_uuid is as it is to make it easier to package into the on-wire format, but
> I suspect there's no problem with using a completely random UUID instead and
> divvying it up the same way.
Maybe like this:
8<----7
>From 9e164f852366750fdd732ae317af9f4a9a04a16e Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@arndb.de>
Date: Wed, 11 Jan 2017 16:53:13 +0100
Subject: [PATCH] afs: use random UUID
AFS uses a time based UUID to identify the host itself. This requires
getting a timestamp which is currently done through the getnstimeofday()
interface that we want to eventually get rid of.
Instead of replacing it with a ktime based interface, this simply
removes the entire function and uses generate_random_uuid() instead,
which has a v4 ("completely random") uuid instead of the time based one.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/fs/afs/main.c b/fs/afs/main.c
index f8188feb03ad..9944770849da 100644
--- a/fs/afs/main.c
+++ b/fs/afs/main.c
@@ -35,49 +35,6 @@ struct afs_uuid afs_uuid;
struct workqueue_struct *afs_wq;
/*
- * get a client UUID
- */
-static int __init afs_get_client_UUID(void)
-{
- struct timespec ts;
- u64 uuidtime;
- u16 clockseq;
- int ret;
-
- /* read the MAC address of one of the external interfaces and construct
- * a UUID from it */
- ret = afs_get_MAC_address(afs_uuid.node, sizeof(afs_uuid.node));
- if (ret < 0)
- return ret;
-
- getnstimeofday(&ts);
- uuidtime = (u64) ts.tv_sec * 1000 * 1000 * 10;
- uuidtime += ts.tv_nsec / 100;
- uuidtime += AFS_UUID_TO_UNIX_TIME;
- afs_uuid.time_low = uuidtime;
- afs_uuid.time_mid = uuidtime >> 32;
- afs_uuid.time_hi_and_version = (uuidtime >> 48) & AFS_UUID_TIMEHI_MASK;
- afs_uuid.time_hi_and_version |= AFS_UUID_VERSION_TIME;
-
- get_random_bytes(&clockseq, 2);
- afs_uuid.clock_seq_low = clockseq;
- afs_uuid.clock_seq_hi_and_reserved =
- (clockseq >> 8) & AFS_UUID_CLOCKHI_MASK;
- afs_uuid.clock_seq_hi_and_reserved |= AFS_UUID_VARIANT_STD;
-
- _debug("AFS UUID: %08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
- afs_uuid.time_low,
- afs_uuid.time_mid,
- afs_uuid.time_hi_and_version,
- afs_uuid.clock_seq_hi_and_reserved,
- afs_uuid.clock_seq_low,
- afs_uuid.node[0], afs_uuid.node[1], afs_uuid.node[2],
- afs_uuid.node[3], afs_uuid.node[4], afs_uuid.node[5]);
-
- return 0;
-}
-
-/*
* initialise the AFS client FS module
*/
static int __init afs_init(void)
@@ -86,9 +43,7 @@ static int __init afs_init(void)
printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 registering.\n");
- ret = afs_get_client_UUID();
- if (ret < 0)
- return ret;
+ generate_random_uuid((unsigned char *)&afs_uuid);
/* create workqueue */
ret = -ENOMEM;
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH] afs: use random UUID
2017-01-11 15:55 ` Arnd Bergmann
@ 2017-01-12 9:27 ` kbuild test robot
0 siblings, 0 replies; 10+ messages in thread
From: kbuild test robot @ 2017-01-12 9:27 UTC (permalink / raw)
To: Arnd Bergmann
Cc: kbuild-all, David Howells, Tina Ruchandani, linux-afs, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 1321 bytes --]
Hi Arnd,
[auto build test ERROR on linus/master]
[also build test ERROR on v4.10-rc3 next-20170111]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Arnd-Bergmann/afs-use-random-UUID/20170112-153644
config: x86_64-randconfig-in0-01121653 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All errors (new ones prefixed by >>):
fs/afs/main.c: In function 'afs_init':
>> fs/afs/main.c:45:2: error: implicit declaration of function 'generate_random_uuid' [-Werror=implicit-function-declaration]
generate_random_uuid((unsigned char *)&afs_uuid);
^~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
vim +/generate_random_uuid +45 fs/afs/main.c
39 static int __init afs_init(void)
40 {
41 int ret;
42
43 printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 registering.\n");
44
> 45 generate_random_uuid((unsigned char *)&afs_uuid);
46
47 /* create workqueue */
48 ret = -ENOMEM;
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 22103 bytes --]
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] AFS: Correctly use 64-bit time for UUID
2015-10-30 8:51 [PATCH] AFS: Correctly use 64-bit time for UUID Tina Ruchandani
@ 2015-11-05 16:25 ` Arnd Bergmann
0 siblings, 0 replies; 10+ messages in thread
From: Arnd Bergmann @ 2015-11-05 16:25 UTC (permalink / raw)
To: Tina Ruchandani; +Cc: linux-afs, dhowells, linux-kernel, y2038
On Friday 30 October 2015 01:51:01 Tina Ruchandani wrote:
> UUID calculation uses 'struct timespec' whose seconds will overflow
> in year 2038 and beyond for 32-bit systems. This patch removes the
> dependency on 'struct timespec' by using ktime_get_real().
> While the patch does not fix a 'bug' as such, it is part of a larger
> effort to remove instances of 'struct timespec' and other data-structures
> suffering from y2038 problem from the kernel.
>
> Suggested-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
David, I'm applying this into my y2038 tree so I don't forget about
it, but I'd prefer if you can pick it up for AFS in 4.5.
Arnd
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] AFS: Correctly use 64-bit time for UUID
@ 2015-10-30 8:51 Tina Ruchandani
2015-11-05 16:25 ` Arnd Bergmann
0 siblings, 1 reply; 10+ messages in thread
From: Tina Ruchandani @ 2015-10-30 8:51 UTC (permalink / raw)
To: linux-afs; +Cc: dhowells, arnd, linux-kernel, y2038
UUID calculation uses 'struct timespec' whose seconds will overflow
in year 2038 and beyond for 32-bit systems. This patch removes the
dependency on 'struct timespec' by using ktime_get_real().
While the patch does not fix a 'bug' as such, it is part of a larger
effort to remove instances of 'struct timespec' and other data-structures
suffering from y2038 problem from the kernel.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
---
Changes in v2:
- Use 64-bit division API, fix 32-bit build
---
fs/afs/main.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/fs/afs/main.c b/fs/afs/main.c
index 35de0c0..129ff43 100644
--- a/fs/afs/main.c
+++ b/fs/afs/main.c
@@ -14,6 +14,7 @@
#include <linux/init.h>
#include <linux/completion.h>
#include <linux/sched.h>
+#include <linux/ktime.h>
#include "internal.h"
MODULE_DESCRIPTION("AFS Client File System");
@@ -37,7 +38,6 @@ struct workqueue_struct *afs_wq;
*/
static int __init afs_get_client_UUID(void)
{
- struct timespec ts;
u64 uuidtime;
u16 clockseq;
int ret;
@@ -48,9 +48,7 @@ static int __init afs_get_client_UUID(void)
if (ret < 0)
return ret;
- getnstimeofday(&ts);
- uuidtime = (u64) ts.tv_sec * 1000 * 1000 * 10;
- uuidtime += ts.tv_nsec / 100;
+ uuidtime = ktime_divns(ktime_get_real(), 100);
uuidtime += AFS_UUID_TO_UNIX_TIME;
afs_uuid.time_low = uuidtime;
afs_uuid.time_mid = uuidtime >> 32;
--
1.9.1
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH] AFS: Correctly use 64-bit time for UUID
2015-01-29 5:53 Tina Ruchandani
@ 2015-02-11 13:52 ` David Howells
0 siblings, 0 replies; 10+ messages in thread
From: David Howells @ 2015-02-11 13:52 UTC (permalink / raw)
To: Tina Ruchandani; +Cc: dhowells, linux-afs, Arnd Bergmann, linux-kernel
Tina Ruchandani <ruchandani.tina@gmail.com> wrote:
> + uuidtime = ktime_get_real_ns() / 100;
64-bit division must be done using asm/div64.h
David
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH] AFS: Correctly use 64-bit time for UUID
@ 2015-01-29 5:53 Tina Ruchandani
2015-02-11 13:52 ` David Howells
0 siblings, 1 reply; 10+ messages in thread
From: Tina Ruchandani @ 2015-01-29 5:53 UTC (permalink / raw)
To: linux-afs; +Cc: Arnd Bergmann, David Howells, linux-kernel
UUID calculation uses 'struct timespec' whose seconds will overflow
in year 2038 and beyond for 32-bit systems. This patch removes the
dependency on 'struct timespec' by using ktime_get_real_ns().
While the patch does not fix a 'bug' as such, it is part of a larger
effort to remove instances of 'struct timespec' and other data-structures
suffering from y2038 problem from the kernel.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
---
fs/afs/main.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/fs/afs/main.c b/fs/afs/main.c
index 35de0c0..7a9c2e6 100644
--- a/fs/afs/main.c
+++ b/fs/afs/main.c
@@ -14,6 +14,7 @@
#include <linux/init.h>
#include <linux/completion.h>
#include <linux/sched.h>
+#include <linux/ktime.h>
#include "internal.h"
MODULE_DESCRIPTION("AFS Client File System");
@@ -37,7 +38,6 @@ struct workqueue_struct *afs_wq;
*/
static int __init afs_get_client_UUID(void)
{
- struct timespec ts;
u64 uuidtime;
u16 clockseq;
int ret;
@@ -48,9 +48,7 @@ static int __init afs_get_client_UUID(void)
if (ret < 0)
return ret;
- getnstimeofday(&ts);
- uuidtime = (u64) ts.tv_sec * 1000 * 1000 * 10;
- uuidtime += ts.tv_nsec / 100;
+ uuidtime = ktime_get_real_ns() / 100;
uuidtime += AFS_UUID_TO_UNIX_TIME;
afs_uuid.time_low = uuidtime;
afs_uuid.time_mid = uuidtime >> 32;
--
2.2.0.rc0.207.ga3a616c
^ permalink raw reply related [flat|nested] 10+ messages in thread
end of thread, other threads:[~2017-01-12 9:27 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-01-11 13:44 [PATCH] afs: correctly use 64-bit time for UUID Arnd Bergmann
2017-01-11 13:51 ` David Howells
2017-01-11 14:03 ` Arnd Bergmann
2017-01-11 14:47 ` David Howells
2017-01-11 15:55 ` Arnd Bergmann
2017-01-12 9:27 ` [PATCH] afs: use random UUID kbuild test robot
-- strict thread matches above, loose matches on Subject: below --
2015-10-30 8:51 [PATCH] AFS: Correctly use 64-bit time for UUID Tina Ruchandani
2015-11-05 16:25 ` Arnd Bergmann
2015-01-29 5:53 Tina Ruchandani
2015-02-11 13:52 ` David Howells
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).