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charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: B447CC0008 X-Stat-Signature: pysxcky9z6iu5wnjhocrhbw3ox31aot9 X-HE-Tag: 1719102675-401538 X-HE-Meta: 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 EBoPlWNG kHpIso4Dvl3hMp7HqWkN9e3jJWouX7Tip9+aWyLeq8ceOkMAocCpZZiALz2n5/dtkYjIS38lBEhEWG0ZhzYHrffU8xH86s4Lr43jFWSeJBag7+zYq+2tBc84yWu7IicPr2MR2423IjcodSb1fe8Wv8vorZ9CVyP9xLr8+gFW9ra74Ulz6QeRMw1qjiWSrBicimdnMiQm9YuRTO9opF3kIEA7scfD5AoPey82XbuUcMfAkQ2VOvxTVFLzY1AFVXzrEx0aBlKu0bVke1JDqf6KP1ML0w2728gwzLv+XtqVR1SU3oQ5nwXkXV5sQuxAmbssWKiHxYoIwLXQ1GwG6M/w/9HXQv4qAJ5s3AGnAhDlkiBAWfctgFAjznC5toT4ah3KD5zrGR3EespdF5WL79wRGSaneRkBUmXQB130ExMc8444UTwJgWWbE7MefIyt1mxDoD9P76Vq9msBk8rKWy7vcoy6d44D7oLdCj91NfSZBVPpvGegvL5BeaZ39mkGSyn19d55g6X913SHlISDqej1lfdiHtRcBtFgDPDFMgyqfLXqiU+2+im4tfgzf0lMFHiHYSMa/9CincJ+iKZTWRUeE6N4Eyxf/a8gz7D70542IHBHnIAM/pYW/qA1XgDM3iCJi8gdbmjC+OpEr6rq4pgzcvRqBhmXr5mesHNkkzW2NQFPk+hOmpDsX5Mv5xx1qV9UO9p9tx10rX+G/7HGz1ywmCxP6uzxMGibPNwonQasG+aZeZvvRspPP8qCz7dFhkPoRPpiav9oSSjCBwqyQKNXcb6QJK57VyDuDDgh8t2uTLgiFdrc= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, Jun 22, 2024 at 09:16:23PM +0300, Mike Rapoport wrote: >(added microblaze maintainer) > >On Fri, Jun 21, 2024 at 09:11:59PM -0700, Guenter Roeck wrote: >> On 6/21/24 16:06, Wei Yang wrote: >> > On Thu, Jun 20, 2024 at 07:34:06PM -0700, Guenter Roeck wrote: >> > > On 6/20/24 18:07, Wei Yang wrote: >> > > > 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 >> > > > > > CC: Paul Mackerras >> > > > > > CC: Tejun Heo >> > > > > > CC: Mike Rapoport >> > > > > > >> > > > > >> > > > > With this patch in linux-next, all microblaze qemu images fail to boot. Reverting it >> > > > > fixes the problem. >> > > >> > > This is a silent failure. There is no console output, so the image crashes >> > > before it gets to that point. >> > > >> > > Building microblaze:petalogix-s3adsp1800:initrd ... running ................R............. failed (silent) >> > > ------------ >> > > qemu log: >> > > qemu-system-microblaze: terminating on signal 15 from pid 2343410 (/bin/bash) >> > >> > Would you mind add kernel parameter memblock=debug without the commit applied? >> > If my understanding is correct, you can bootup without this commit, right? >> >> Yes. With this change on top of linux-next: >> >> diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c >> index 3827dc76edd8..1d3edac064ee 100644 >> --- a/arch/microblaze/mm/init.c >> +++ b/arch/microblaze/mm/init.c >> @@ -195,7 +195,9 @@ asmlinkage void __init mmu_init(void) >> >> if (!memblock.reserved.cnt) { > >I tried to understand what this was supposed to check, but this test was >there from day 1, so git archaeology didn't help :( > >Anyway, it's perfectly fine to have any number of memblock reservations >here or no at all. > >early_init_devtree() is called before mmu_init() and it sets up >memblock.memory via early_init_dt_scan() and even allows memblock >allocations. So the check for !memblock.reserved.cnt here seems wrong. > >> pr_emerg("Error memory count\n"); >> +#if 0 >> machine_restart(NULL); >> +#endif >> } >> >> the log starts with: >> >> random: crng init done >> Ramdisk addr 0x51923788, >> FDT at 0x51f43d88 >> Error memory count >> MEMBLOCK configuration: >> memory size = 0x10000000 reserved size = 0x015bb600 >> memory.cnt = 0x1 >> memory[0x0] [0x50000000-0x5fffffff], 0x10000000 bytes flags: 0x0 >> reserved.cnt = 0x3 >> reserved[0x0] [0x50000000-0x50f5cfff], 0x00f5d000 bytes flags: 0x0 >> reserved[0x1] [0x510c0000-0x510fffff], 0x00040000 bytes flags: 0x0 >> reserved[0x2] [0x51923788-0x51f41d87], 0x0061e600 bytes flags: 0x0 >> Linux version 6.10.0-rc4-next-20240620-dirty (groeck@server.roeck-us.net) (microblaze-linux-gcc (GCC) 11.4.0, GNU ld (GNU Binutils) 2.40) #1 Fri Jun 21 21:00:40 PDT 2024 >> setup_memory: max_mapnr: 0x10000 >> setup_memory: min_low_pfn: 0x50000 >> setup_memory: max_low_pfn: 0x60000 >> setup_memory: max_pfn: 0x60000 >> memblock_alloc_try_nid: 4096 bytes align=0x1000 nid=-1 from=0x00000000 max_addr=0x51100000 pte_alloc_one_kernel+0x50/0x64 >> memblock_reserve: [0x510bf000-0x510bffff] memblock_alloc_range_nid+0x104/0x1d4 >> >> Guenter > >I think simply removing the check for !memblock.reserved.cnt is the right >thing to do here: > >>>From 975c5ba011330238444c82d0b171779c2156d2dc Mon Sep 17 00:00:00 2001 >From: "Mike Rapoport (IBM)" >Date: Sat, 22 Jun 2024 20:46:36 +0300 >Subject: [PATCH] microblaze: don't treat zero reserved memory regions as error > >Before commit 721f4a6526da ("mm/memblock: remove empty dummy entry") the >check for non-zero of memblock.reserved.cnt in mmu_init() would always >be true either because memblock.reserved.cnt is initialized to 1 or >because there were memory reservations earlier. > >The removal of dummy empty entry in memblock caused this check to fail >because now memblock.reserved.cnt is initialized to 0. > >Remove the check for non-zero of memblock.reserved.cnt because it's >perfectly fine to have an empty memblock.reserved array that early in >boot. > >Reported-by: Guenter Roeck >Signed-off-by: Mike Rapoport (IBM) Thanks Mike :-) Reviewed-by: Wei Yang >--- > arch/microblaze/mm/init.c | 5 ----- > 1 file changed, 5 deletions(-) > >diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c >index 3827dc76edd8..4520c5741579 100644 >--- a/arch/microblaze/mm/init.c >+++ b/arch/microblaze/mm/init.c >@@ -193,11 +193,6 @@ asmlinkage void __init mmu_init(void) > { > unsigned int kstart, ksize; > >- if (!memblock.reserved.cnt) { >- pr_emerg("Error memory count\n"); >- machine_restart(NULL); >- } >- > if ((u32) memblock.memory.regions[0].size < 0x400000) { > pr_emerg("Memory must be greater than 4MB\n"); > machine_restart(NULL); >-- >2.43.0 > > >-- >Sincerely yours, >Mike. -- Wei Yang Help you, Help me