diff options
| author | Ilpo Järvinen <[email protected]> | 2006-08-04 23:36:18 +0000 |
|---|---|---|
| committer | David S. Miller <[email protected]> | 2006-08-05 05:59:51 +0000 |
| commit | c4c0ce5c57ef0ca47a4428a14de6b5c8cdf8de8a (patch) | |
| tree | 762530925f75495b9d2b8bb35702060e7e2fa9ae /net/lapb/lapb_iface.c | |
| parent | [LLX]: SOCK_DGRAM interface fixes (diff) | |
| download | kernel-c4c0ce5c57ef0ca47a4428a14de6b5c8cdf8de8a.tar.gz kernel-c4c0ce5c57ef0ca47a4428a14de6b5c8cdf8de8a.zip | |
[PKT_SCHED] RED: Fix overflow in calculation of queue average
Overflow can occur very easily with 32 bits, e.g., with 1 second
us_idle is approx. 2^20, which leaves only 11-Wlog bits for queue
length. Since the EWMA exponent is typically around 9, queue
lengths larger than 2^2 cause overflow. Whether the affected
branch is taken when us_idle is as high as 1 second, depends on
Scell_log, but with rather reasonable configuration Scell_log is
large enough to cause p->Stab to have zero index, which always
results zero shift (typically also few other small indices result
in zero shift).
Signed-off-by: Ilpo Järvinen <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Diffstat (limited to 'net/lapb/lapb_iface.c')
0 files changed, 0 insertions, 0 deletions