On Thu, Apr 29, 2021 at 07:21:13AM -0700, Dave Hansen wrote: > On 4/29/21 12:03 AM, Tian Tao wrote: > > diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node > > index 484fc04..82dfe64 100644 > > --- a/Documentation/ABI/stable/sysfs-devices-node > > +++ b/Documentation/ABI/stable/sysfs-devices-node > > @@ -47,7 +47,10 @@ What: /sys/devices/system/node/nodeX/cpulist > > Date: October 2002 > > Contact: Linux Memory Management list <linux-mm@xxxxxxxxx> > > Description: > > - The CPUs associated to the node. > > + The CPUs associated to the node. The format is like 0-3, > > + 8-11, 14,17. maximum size is PAGE_SIZE, so the tail > > + of the string will be trimmed while its size is larger > > + than PAGE_SIZE. > > I think it's pretty arguable that truncating output on a real system is > an ABI break. Doing this would make the interface rather useless. > > Don't we need a real solution rather than throwing up our hands? > > Do we think >PAGE_SIZE data out of a sysfs file is a worse ABI break or > something? There is a real way to get > PAGE_SIZE out of a sysfs file. The LED developers had to do this when they ran into this same exact problem. Make it a binary sysfs file and promise to NEVER create such a file again in the future :) thanks, gre gk-h
