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DIR:OUT; SFP:1102; SCL:1; SRVR:BY5PR18MB3347; H:BY5PR18MB3188.namprd18.prod.outlook.com; FPR:; SPF:None; LANG:en; PTR:InfoNoRecords; MX:1; A:1; Received-SPF: None (protection.outlook.com: suse.com does not designate permitted sender hosts) X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-MS-Exchange-AntiSpam-MessageData: Pk8hPR303Qe1zi1hSOPMxydY1BJKpYw09bpD/Jbz2qytGtsb2jqC1zz7uYSQVtutE0KdErVkB5JKzvq4+iVbncHjADLmqGjjysiQbgoMvgOrTgWKhajPJ5SjCoi5MtOzDTO7uhq1lka82rB705ux2g== X-MS-Exchange-CrossTenant-Network-Message-Id: a9b7b15e-838d-4090-19c0-08d7c1847da6 X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Mar 2020 04:11:49.1481 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 856b813c-16e5-49a5-85ec-6f081e13b527 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: DfjapftzcvBBwXqocafIP/KGU6I4PKm98X1FyWnTlrq5VMm/wzBTXp1V+jWnooIT X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR18MB3347 X-OriginatorOrg: suse.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 15.124.64.91 X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: The development of GNU GRUB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 06 Mar 2020 04:12:33 -0000 On Thu, Mar 05, 2020 at 03:38:20PM +0100, Daniel Kiper wrote: > On Thu, Mar 05, 2020 at 06:40:01PM +0800, Michael Chang wrote: > > Further to the discussion about disabling btrfs zstd support for > > i386-pc[1], this paragraph in manual about mbr gap size doesn't seem to > > hold true any longer. > > > > "You must ensure that the first partition starts at least 31 KiB (63 > > sectors) from the start of the disk" > > > > As in many occasions we inevitablely have to provide core image size > > that goes beyond 31 KiB, this statement becomes a true liability as > > people would be misguided and think it is still fine to use small MBR > > gap, that has always been a headache in distribution's upgrade path as > > growing new feature would render the size requirement bigger but no way > > for the user to relocate their partitions. > > Could you split this paragraph into a few sentences? Now it does not > read very well... OK. I'll come up with a better expression next version. > > > The patch tries to correct the paragraph with a more practical size that > > works for grub and also for modern computer systems in general. > > > > [1] https://lists.gnu.org/archive/html/grub-devel/2019-11/msg00025.html > > > > Signed-off-by: Michael Chang > > --- > > docs/grub.texi | 20 ++++++++++++++------ > > 1 file changed, 14 insertions(+), 6 deletions(-) > > > > diff --git a/docs/grub.texi b/docs/grub.texi > > index 83979af38..651468268 100644 > > --- a/docs/grub.texi > > +++ b/docs/grub.texi > > @@ -845,12 +845,20 @@ only be used if the @file{/boot} filesystem is on the same disk that the > > BIOS boots from, so that GRUB does not have to rely on guessing BIOS drive > > numbers. > > > > -The GRUB development team generally recommends embedding GRUB before the > > -first partition, unless you have special requirements. You must ensure that > > -the first partition starts at least 31 KiB (63 sectors) from the start of > > -the disk; on modern disks, it is often a performance advantage to align > > -partitions on larger boundaries anyway, so the first partition might start 1 > > -MiB from the start of the disk. > > +The GRUB development team generally recommends embedding GRUB before the first > > +partition, unless you have special requirements. You must ensure that the first > > +partition starts at least 1 MiB from the start of the disk; on modern disks, it > > s/; on modern disks, it/. Additionally, on modern disks it/ OK. > > > +is often a performance advantage to align partitions on larger boundaries and 1 > > +MiB is the least common multiple of many used alignment sizes. For SSD, it > > s/For SSD, it/E.g. SSD, it/ OK. > > > +became crucial to have the partition correctly aligned to avoid excessive > > +read-modify-write cycles and thus modern tools set to use 1 MiB as a stardard > > +practice. > > + > > +In case legacy systems that cannot boot if first partition not on the cylinder > > s/In case legacy/In case of legacy/ > s/partition not/partition is not/ OK. > > > +boundary, the fallback blocklist install method should remain working for them > > +if the core image growing too much someday. Here we just can't advertise that > > +31 KiB (63 sectors) is a sensible size any longer as that would pose great > > +constraint to include new features as time goes by. Thanks a lot for taking time to review. Regards, Michael > > Daniel > > _______________________________________________ > Grub-devel mailing list > Grub-devel@gnu.org > https://lists.gnu.org/mailman/listinfo/grub-devel