On Thu, Jun 20, 2024 at 02:58:17PM -0700, Guenter Roeck wrote: >Hi, > >On Fri, Apr 05, 2024 at 01:58:21AM +0000, Wei Yang wrote: >> The dummy entry is introduced in the initial implementation of lmb in >> commit 7c8c6b9776fb ("powerpc: Merge lmb.c and make MM initialization >> use it."). >> >> As the comment says the empty dummy entry is to simplify the code. >> >> /* Create a dummy zero size LMB which will get coalesced away later. >> * This simplifies the lmb_add() code below... >> */ >> >> While current code is reimplemented by Tejun in commit 784656f9c680 >> ("memblock: Reimplement memblock_add_region()"). This empty dummy entry >> seems not benefit the code any more. >> >> Let's remove it. >> >> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx> >> CC: Paul Mackerras <paulus@xxxxxxxxxx> >> CC: Tejun Heo <tj@xxxxxxxxxx> >> CC: Mike Rapoport <rppt@xxxxxxxxxx> >> > >With this patch in linux-next, all microblaze qemu images fail to boot. Reverting it >fixes the problem. > >Bisect log is attached for reference. > Thanks for the reporting. Would you mind running the test to take a look? It is in tools/testing/memblock. Simply make and ./main. >Guenter > >--- ># bad: [2102cb0d050d34d50b9642a3a50861787527e922] Add linux-next specific files for 20240619 ># good: [6ba59ff4227927d3a8530fc2973b80e94b54d58f] Linux 6.10-rc4 >git bisect start 'HEAD' 'v6.10-rc4' ># good: [a8fa5261ec87d5aafd3211548d93008d5739457d] Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git >git bisect good a8fa5261ec87d5aafd3211548d93008d5739457d ># good: [ee551f4db89753511a399b808db75654facec7c8] Merge branch 'for-linux-next' of https://gitlab.freedesktop.org/drm/i915/kernel >git bisect good ee551f4db89753511a399b808db75654facec7c8 ># good: [ec3557f4b791d72d93bfb69702d441d2c9f8cd0d] Merge branch 'next' of git://git.kernel.org/pub/scm/virt/kvm/kvm.git >git bisect good ec3557f4b791d72d93bfb69702d441d2c9f8cd0d ># good: [48d51b3acbb237074014d498d76ea6b6ce5aed69] Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/phy/linux-phy.git >git bisect good 48d51b3acbb237074014d498d76ea6b6ce5aed69 ># good: [59972b98583cd97febf9ecc576a706a7c5046278] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl.git >git bisect good 59972b98583cd97febf9ecc576a706a7c5046278 ># good: [49aa15d761ce8976bb131f06886e89bd10cdb9fd] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching >git bisect good 49aa15d761ce8976bb131f06886e89bd10cdb9fd ># bad: [129b9b07cd69885a804319c3fac82ef79e012e07] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock.git >git bisect bad 129b9b07cd69885a804319c3fac82ef79e012e07 ># good: [344db92cbecc8da1f58d559926c61ceb72e72a03] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/srini/nvmem.git >git bisect good 344db92cbecc8da1f58d559926c61ceb72e72a03 ># bad: [ce8ebb95439459f7e24b02c6943e278f46d2d328] mm/mm_init.c: get the highest zone directly >git bisect bad ce8ebb95439459f7e24b02c6943e278f46d2d328 ># bad: [1a879671bdfd14698a839f30de8e6d76e1e858fd] memblock tests: add memblock_overlaps_region_checks >git bisect bad 1a879671bdfd14698a839f30de8e6d76e1e858fd ># bad: [3d3165193776ddacf59f101f0fa05cfab9f1a9ba] memblock tests: add memblock_reserve_all_locations_check() >git bisect bad 3d3165193776ddacf59f101f0fa05cfab9f1a9ba ># bad: [721f4a6526daafca15634f30c9865e880da3e1d1] mm/memblock: remove empty dummy entry >git bisect bad 721f4a6526daafca15634f30c9865e880da3e1d1 ># first bad commit: [721f4a6526daafca15634f30c9865e880da3e1d1] mm/memblock: remove empty dummy entry -- Wei Yang Help you, Help me