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| author |   Jacob Keller <jacob.e.keller@intel.com> | 2019-02-25 11:20:05 -0800 |
|---|---|---|
| committer |   Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2019-03-26 15:14:04 -0700 |
| commit | b3ccbbce1e455b8454d3935eb9ae0a5f18939e24 (patch) | |
| tree | 307463071e77c042e79a5312a51100ccaada3652 /drivers/net | |
| parent | dpaa2-eth: fix race condition with bql frame accounting (diff) | |
| download | linux-dev-b3ccbbce1e455b8454d3935eb9ae0a5f18939e24.tar.xz linux-dev-b3ccbbce1e455b8454d3935eb9ae0a5f18939e24.zip | |
i40e: fix i40e_ptp_adjtime when given a negative delta
Commit 0ac30ce43323 ("i40e: fix up 32 bit timespec references",
2017-07-26) claims to be cleaning up references to 32-bit timespecs.
The actual contents of the commit make no sense, as it converts a call
to timespec64_add into timespec64_add_ns. This would seem ok, if (a) the
change was documented in the commit message, and (b) timespec64_add_ns
supported negative numbers.
timespec64_add_ns doesn't work with signed deltas, because the
implementation is based around iter_div_u64_rem. This change resulted in
a regression where i40e_ptp_adjtime would interpret small negative
adjustments as large positive additions, resulting in incorrect
behavior.
This commit doesn't appear to fix anything, is not well explained, and
introduces a bug, so lets just revert it.
Reverts: 0ac30ce43323 ("i40e: fix up 32 bit timespec references", 2017-07-26)
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/ethernet/intel/i40e/i40e_ptp.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ptp.c b/drivers/net/ethernet/intel/i40e/i40e_ptp.c index 5fb4353c742b..31575c0bb884 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_ptp.c +++ b/drivers/net/ethernet/intel/i40e/i40e_ptp.c @@ -146,12 +146,13 @@ static int i40e_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) static int i40e_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) { struct i40e_pf *pf = container_of(ptp, struct i40e_pf, ptp_caps); - struct timespec64 now; + struct timespec64 now, then; + then = ns_to_timespec64(delta); mutex_lock(&pf->tmreg_lock); i40e_ptp_read(pf, &now, NULL); - timespec64_add_ns(&now, delta); + now = timespec64_add(now, then); i40e_ptp_write(pf, (const struct timespec64 *)&now); mutex_unlock(&pf->tmreg_lock); |