Re: [PATCH 01/19] btrfs: require at least 4 devices for RAID 6
Qu Wenruo <[email protected]>
| Newsgroups | gmane.linux.ports.riscv,gmane.linux.kernel,gmane.linux.ports.arm.kernel,gmane.linux.ports.ppc64.devel,gmane.linux.kernel.cryptoapi,gmane.comp.file-systems.btrfs,gmane.linux.kernel.cross-arch,gmane.linux.raid |
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| Message-ID | <[email protected]> |
在 2026/5/18 14:42, Christoph Hellwig 写道: > On Fri, May 15, 2026 at 12:59:34PM -0700, H. Peter Anvin wrote: >> I don't think this is a good idea. Error out; it is the btrfs maintainers' job to ensure user data isn't lost. >> >> The RAID-6 code has *never* supported only 3 units, and if it ever worked for *any* of the implementations it was purely by accident. Speaking as the original author I should know; this was deliberate as in some cases the degenerate case (3) would have required extra trays in the code to no user benefit. >> >> I would not be surprised if the kernel crashed or corrupted the page cache in that case. > > It does, that's why I wanted to exclude it. Anyway, for the about to be > resent version I'll drop this btrfs patch over the stated objection and > will otherwise not change anything. This means the (IMHO hypothetical) > users of this configuration will get a WARN_ON_ONCE triggered, but > otherwise keep working (or rather not working) as before. > For the btrfs part, I believe I can get the current 2-disk-raid5 and 3-disk-raid6 to fallback to raid1 inside btrfs. I hope the btrfs part can be finished and reach the next merge window, but I'm not 100% sure. What is the planned cycle to merge this raid5/6 cleanup? Thanks, Qu _______________________________________________ linux-riscv mailing list [email protected] http://lists.infradead.org/mailman/listinfo/linux-riscv