On Fri, 26 May 2023 13:24:04 -0700 stan via kernel <kernel@xxxxxxxxxxxxxxxxxxxxxxx> wrote: > On Fri, 26 May 2023 12:36:18 -0700 > stan via kernel <kernel@xxxxxxxxxxxxxxxxxxxxxxx> wrote: > > > I compile a custom kernel (currently 6.4 rc1), and I have > > CONFIG_PROC_SYSCTL=y > > set in the configuration. I run a program that gathers entropy from > > the atmosphere and feeds it into the kernel entropy pool via the > > public kernel interface. When I start the program, I want to change > > the thresholds for entropy because there is no longer any shortage > > of entropy, so I want it to be kept full (4096). I do that using > > /usr/bin/echo 3967 > /proc/sys/kernel/random/write_wakeup_threshold > > I haven't checked in a while using > > cat /proc/sys/kernel/random/entropy_avail > > It used to hover around 4030 or so. But now the > > write_wakeup_threshold is 256, and the amount of entropy is 256, and > > no changes are possible. > > > > Have there been recent changes to the kernel random generation > > process? Has this been deprecated or restricted? > > It seems that this is a known issue, and I am not the only one > affected. It is > discussed in the link > below. > https://github.com/nhorman/rng-tools/issues/173 I see this from the author of LRNG. "The following patch set provides a different approach to /dev/random which is called Linux Random Number Generator (LRNG) to collect entropy within the Linux kernel. It provides the same API and ABI and can be used as a drop-in replacement." Obviously, the last sentence is false, since it caused the user input of entropy to the kernel to fail, because it changed the process. It removed the two proc/sys values as having any relevance. I'll have to see if I can ditch this LRNG since I don't need it, and from the thread above, it doesn't seem like it will work for individuals wanting to add entropy. I completely missed any discussion of this. It's too bad the author didn't add it in a way that didn't interfere with existing functionality. _______________________________________________ kernel mailing list -- kernel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to kernel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/kernel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
