On Fri, Jun 23, 2023 at 02:52:25PM -0700, Linus Torvalds wrote:
On Fri, 23 Jun 2023 at 13:31, Jason A. Donenfeld Jason@zx2c4.com wrote:
We always have to write when using so that we don't credit the same seed twice, so it's gotta be used at a stage when SetVariable is somewhat working.
This code isn't even the code that "uses" the alleged entropy from that EFI variable in the first place. That's the code in efi_random_get_seed() in the EFI boot sequence, and appends it to the bootup randomness buffers.
And that code already seems to clear the EFI variable (or seems to append to it).
Oh, doh, yea, you're right. Sorry. My mistake.
So indeed, we can probably get away with just delaying this until much later in boot, and doing this inside of a workqueue or similar, instead of in some special early boot context. Or maybe shutdown? Shutdown seems like it'd better handle potential firmware issues since hanging on shutdown is a lot better than hanging on boot. But it would be nice to keep this working during unclean shutdown, which maybe means doing it sometime after bootup is still better.
So this argument seems to be complete garbage - we absolutely do not have to write it, and your patch already just wrote it in the wrong place anyway.
Don't make excuses. That code caused boot failures, it was all done in the wrong place, and at entirely the wrong time.
Yes, my point was entirely wrong. I was mistaken. But it wasn't an *excuse*. I was just momentarily confused. No malice here, I promise.
Jason