* powerpc/fadump: CMA init is failing @ 2026-02-27 15:19 Sourabh Jain 2026-02-27 17:09 ` Ritesh Harjani 0 siblings, 1 reply; 6+ messages in thread From: Sourabh Jain @ 2026-02-27 15:19 UTC (permalink / raw) To: Ritesh Harjani (IBM), Madhavan Srinivasan, linuxppc-dev, Michael Ellerman Cc: Donet Tom, Hari Bathini, Mahesh J Salgaonkar I noticed CMA init for fadump crashkernel memory is failing. [ 0.000000] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000] fadump: Failed to init cma area for firmware-assisted dump,-22 kernel command-line: BOOT_IMAGE=(ieee1275//vdevice/v-scsi@30000070/disk@8100000000000000,msdos2)/vmlinuz-7.0.0-rc1+ root=/dev/mapper/rhel_ltcden3--lp12-root ro rd.lvm.lv=rhel_ltcden3-lp12/root rd.lvm.lv=rhel_ltcden3-lp12/swap fadump=on crashkernel=3G Same issue with kdump CMA reservation: [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 200 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 100 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 50 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 25 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 12 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 6 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 3 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 1 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 0 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 0 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 0 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 0 MiB [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called during early boot? [ 0.000000][ T0] cma: Failed to reserve 0 MiB [ 0.000000][ T0] crashkernel CMA reservation failed: 200 MB requested, 0 MB reserved in 0 ranges kernel command-line: # cat /proc/cmdline noreboot crashkernel=200M crashkernel=200M,cma Should be easy to reproduce it with powerpc defconfig: make ARCH=powerpc defconfig The crashkernel CMA init for fadump and kdump happens in: arch/powerpc/kernel/setup-common.c -> setup_arch() initmem_init(); /* * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM and * hugetlb. These must be called after initmem_init(), so that * pageblock_order is initialised. */ fadump_cma_init(); kdump_cma_reserve(); kvm_cma_reserve(); Has something changed for pageblock_order initialization? - Sourabh Jain ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: powerpc/fadump: CMA init is failing 2026-02-27 15:19 powerpc/fadump: CMA init is failing Sourabh Jain @ 2026-02-27 17:09 ` Ritesh Harjani 2026-02-27 20:50 ` Mike Rapoport 0 siblings, 1 reply; 6+ messages in thread From: Ritesh Harjani @ 2026-02-27 17:09 UTC (permalink / raw) To: Sourabh Jain, Madhavan Srinivasan, linuxppc-dev, Michael Ellerman, Mike Rapoport Cc: Donet Tom, Hari Bathini, Mahesh J Salgaonkar, linux-mm Sourabh Jain <sourabhjain@linux.ibm.com> writes: > I noticed CMA init for fadump crashkernel memory is failing. > > [ 0.000000] cma: pageblock_order not yet initialized. Called during > early boot? > [ 0.000000] fadump: Failed to init cma area for firmware-assisted > dump,-22 > > > kernel command-line: > BOOT_IMAGE=(ieee1275//vdevice/v-scsi@30000070/disk@8100000000000000,msdos2)/vmlinuz-7.0.0-rc1+ > root=/dev/mapper/rhel_ltcden3--lp12-root ro > rd.lvm.lv=rhel_ltcden3-lp12/root rd.lvm.lv=rhel_ltcden3-lp12/swap > fadump=on crashkernel=3G > > > Same issue with kdump CMA reservation: > > [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called > during early boot? Good that we added those debug prints ;) I think I know what went wrong, as part of this arch,mm consolidation patch series [1], I think the order of initialization is changed. With this patch the new order is ... start_kernel() - setup_arch() - xxx_cma_reserve(); - mm_core_init_early() - free_area_init() - sparse_init() - set_pageblock_order() // this sets the pageblock_order. Whereas earlier set_pageblock_order() was called from initmem_init(), just before cma reservations were being made. start_kernel() - setup_arch() - initmem_init() - sparse_init() - set_pageblock_order(); // this sets the pageblock_order - xxx_cma_reserve(); So that means, pageblock_order is not initialized before these cma reservation function calls, hence we are seeing these failures. setup_arch() { ... /* * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM and * hugetlb. These must be called after initmem_init(), so that * pageblock_order is initialised. */ fadump_cma_init(); kdump_cma_reserve(); kvm_cma_reserve(); ... } So what if we do.. start_kernel() { ... setup_arch(&command_line); mm_core_init_early(); setup_arch_post_mm_core_init(); // and here we call CMA reservation functions ? References: [1]: https://lore.kernel.org/linuxppc-dev/20260111082105.290734-1-rppt@kernel.org/T/#m5adf1a845e0a0867066c4f7055f28e6304b73fa5 [2]: https://lore.kernel.org/all/3ae208e48c0d9cefe53d2dc4f593388067405b7d.1729146153.git.ritesh.list@gmail.com/ -ritesh ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: powerpc/fadump: CMA init is failing 2026-02-27 17:09 ` Ritesh Harjani @ 2026-02-27 20:50 ` Mike Rapoport 2026-02-28 2:35 ` Ritesh Harjani 0 siblings, 1 reply; 6+ messages in thread From: Mike Rapoport @ 2026-02-27 20:50 UTC (permalink / raw) To: Ritesh Harjani Cc: Sourabh Jain, Madhavan Srinivasan, linuxppc-dev, Michael Ellerman, Donet Tom, Hari Bathini, Mahesh J Salgaonkar, linux-mm Hi Ritesh, On Fri, Feb 27, 2026 at 10:39:53PM +0530, Ritesh Harjani wrote: > Sourabh Jain <sourabhjain@linux.ibm.com> writes: > > > I noticed CMA init for fadump crashkernel memory is failing. > > > > [ 0.000000] cma: pageblock_order not yet initialized. Called during > > early boot? > > [ 0.000000] fadump: Failed to init cma area for firmware-assisted > > dump,-22 > > > > > > kernel command-line: > > BOOT_IMAGE=(ieee1275//vdevice/v-scsi@30000070/disk@8100000000000000,msdos2)/vmlinuz-7.0.0-rc1+ > > root=/dev/mapper/rhel_ltcden3--lp12-root ro > > rd.lvm.lv=rhel_ltcden3-lp12/root rd.lvm.lv=rhel_ltcden3-lp12/swap > > fadump=on crashkernel=3G > > > > > > Same issue with kdump CMA reservation: > > > > [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called > > during early boot? > > Good that we added those debug prints ;) > > I think I know what went wrong, as part of this arch,mm consolidation > patch series [1], I think the order of initialization is changed. > > With this patch the new order is ... > start_kernel() > - setup_arch() > - xxx_cma_reserve(); > - mm_core_init_early() > - free_area_init() > - sparse_init() > - set_pageblock_order() // this sets the pageblock_order. > > Whereas earlier set_pageblock_order() was called from initmem_init(), > just before cma reservations were being made. > > start_kernel() > - setup_arch() > - initmem_init() > - sparse_init() > - set_pageblock_order(); // this sets the pageblock_order > - xxx_cma_reserve(); > > So that means, pageblock_order is not initialized before these cma > reservation function calls, hence we are seeing these failures. > > setup_arch() { > ... > > /* > * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM and > * hugetlb. These must be called after initmem_init(), so that > * pageblock_order is initialised. > */ > fadump_cma_init(); > kdump_cma_reserve(); > kvm_cma_reserve(); > > ... > } > > > So what if we do.. > > start_kernel() { > ... > setup_arch(&command_line); > mm_core_init_early(); > setup_arch_post_mm_core_init(); // and here we call CMA reservation functions ? Unless I'm missing something these cma reservations can be moved to arch_mm_preinit(). It runs after mm_core_init_early() and before memblock moves the free memory to the buddy. > References: > [1]: https://lore.kernel.org/linuxppc-dev/20260111082105.290734-1-rppt@kernel.org/T/#m5adf1a845e0a0867066c4f7055f28e6304b73fa5 > [2]: https://lore.kernel.org/all/3ae208e48c0d9cefe53d2dc4f593388067405b7d.1729146153.git.ritesh.list@gmail.com/ > > > -ritesh -- Sincerely yours, Mike. ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: powerpc/fadump: CMA init is failing 2026-02-27 20:50 ` Mike Rapoport @ 2026-02-28 2:35 ` Ritesh Harjani 2026-02-28 13:46 ` Sourabh Jain 0 siblings, 1 reply; 6+ messages in thread From: Ritesh Harjani @ 2026-02-28 2:35 UTC (permalink / raw) To: Mike Rapoport, Sourabh Jain Cc: Madhavan Srinivasan, linuxppc-dev, Michael Ellerman, Donet Tom, Hari Bathini, Mahesh J Salgaonkar, linux-mm Mike Rapoport <rppt@kernel.org> writes: > Hi Ritesh, > > On Fri, Feb 27, 2026 at 10:39:53PM +0530, Ritesh Harjani wrote: >> Sourabh Jain <sourabhjain@linux.ibm.com> writes: >> >> > I noticed CMA init for fadump crashkernel memory is failing. >> > >> > [ 0.000000] cma: pageblock_order not yet initialized. Called during >> > early boot? >> > [ 0.000000] fadump: Failed to init cma area for firmware-assisted >> > dump,-22 >> > >> > >> > kernel command-line: >> > BOOT_IMAGE=(ieee1275//vdevice/v-scsi@30000070/disk@8100000000000000,msdos2)/vmlinuz-7.0.0-rc1+ >> > root=/dev/mapper/rhel_ltcden3--lp12-root ro >> > rd.lvm.lv=rhel_ltcden3-lp12/root rd.lvm.lv=rhel_ltcden3-lp12/swap >> > fadump=on crashkernel=3G >> > >> > >> > Same issue with kdump CMA reservation: >> > >> > [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called >> > during early boot? >> >> Good that we added those debug prints ;) >> >> I think I know what went wrong, as part of this arch,mm consolidation >> patch series [1], I think the order of initialization is changed. >> >> With this patch the new order is ... >> start_kernel() >> - setup_arch() >> - xxx_cma_reserve(); >> - mm_core_init_early() >> - free_area_init() >> - sparse_init() >> - set_pageblock_order() // this sets the pageblock_order. >> >> Whereas earlier set_pageblock_order() was called from initmem_init(), >> just before cma reservations were being made. >> >> start_kernel() >> - setup_arch() >> - initmem_init() >> - sparse_init() >> - set_pageblock_order(); // this sets the pageblock_order >> - xxx_cma_reserve(); >> >> So that means, pageblock_order is not initialized before these cma >> reservation function calls, hence we are seeing these failures. >> >> setup_arch() { >> ... >> >> /* >> * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM and >> * hugetlb. These must be called after initmem_init(), so that >> * pageblock_order is initialised. >> */ >> fadump_cma_init(); >> kdump_cma_reserve(); >> kvm_cma_reserve(); >> >> ... >> } >> >> >> So what if we do.. >> >> start_kernel() { >> ... >> setup_arch(&command_line); >> mm_core_init_early(); >> setup_arch_post_mm_core_init(); // and here we call CMA reservation functions ? > > Unless I'm missing something these cma reservations can be moved to > arch_mm_preinit(). > It runs after mm_core_init_early() and before memblock moves the free > memory to the buddy. > Right. I think, we should be able to use that... @Sourabh, I don't have access to the systems (travelling back...). Could you please give this a try? diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index cb5b73adc250..b1761909c23f 100644 --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -35,7 +35,6 @@ #include <linux/of_irq.h> #include <linux/hugetlb.h> #include <linux/pgtable.h> -#include <asm/kexec.h> #include <asm/io.h> #include <asm/paca.h> #include <asm/processor.h> @@ -995,15 +994,6 @@ void __init setup_arch(char **cmdline_p) initmem_init(); - /* - * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM and - * hugetlb. These must be called after initmem_init(), so that - * pageblock_order is initialised. - */ - fadump_cma_init(); - kdump_cma_reserve(); - kvm_cma_reserve(); - early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); if (ppc_md.setup_arch) diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 29bf347f6012..5ba947e4fe37 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -30,6 +30,10 @@ #include <asm/setup.h> #include <asm/fixmap.h> +#include <asm/fadump.h> +#include <asm/kexec.h> +#include <asm/kvm_ppc.h> + #include <mm/mmu_decl.h> unsigned long long memory_limit __initdata; @@ -268,6 +272,16 @@ void __init paging_init(void) void __init arch_mm_preinit(void) { + + /* + * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM + * and hugetlb. These must be called after pageblock_order is + * initialised. + */ + fadump_cma_init(); + kdump_cma_reserve(); + kvm_cma_reserve(); + /* * book3s is limited to 16 page sizes due to encoding this in * a 4-bit field for slices. -ritesh >> References: >> [1]: https://lore.kernel.org/linuxppc-dev/20260111082105.290734-1-rppt@kernel.org/T/#m5adf1a845e0a0867066c4f7055f28e6304b73fa5 >> [2]: https://lore.kernel.org/all/3ae208e48c0d9cefe53d2dc4f593388067405b7d.1729146153.git.ritesh.list@gmail.com/ >> >> >> -ritesh > > -- > Sincerely yours, > Mike. ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: powerpc/fadump: CMA init is failing 2026-02-28 2:35 ` Ritesh Harjani @ 2026-02-28 13:46 ` Sourabh Jain 2026-02-28 17:54 ` Ritesh Harjani 0 siblings, 1 reply; 6+ messages in thread From: Sourabh Jain @ 2026-02-28 13:46 UTC (permalink / raw) To: Ritesh Harjani (IBM), Mike Rapoport Cc: Madhavan Srinivasan, linuxppc-dev, Michael Ellerman, Donet Tom, Hari Bathini, Mahesh J Salgaonkar, linux-mm Hello Ritesh, On 28/02/26 08:05, Ritesh Harjani (IBM) wrote: > Mike Rapoport <rppt@kernel.org> writes: > >> Hi Ritesh, >> >> On Fri, Feb 27, 2026 at 10:39:53PM +0530, Ritesh Harjani wrote: >>> Sourabh Jain <sourabhjain@linux.ibm.com> writes: >>> >>>> I noticed CMA init for fadump crashkernel memory is failing. >>>> >>>> [ 0.000000] cma: pageblock_order not yet initialized. Called during >>>> early boot? >>>> [ 0.000000] fadump: Failed to init cma area for firmware-assisted >>>> dump,-22 >>>> >>>> >>>> kernel command-line: >>>> BOOT_IMAGE=(ieee1275//vdevice/v-scsi@30000070/disk@8100000000000000,msdos2)/vmlinuz-7.0.0-rc1+ >>>> root=/dev/mapper/rhel_ltcden3--lp12-root ro >>>> rd.lvm.lv=rhel_ltcden3-lp12/root rd.lvm.lv=rhel_ltcden3-lp12/swap >>>> fadump=on crashkernel=3G >>>> >>>> >>>> Same issue with kdump CMA reservation: >>>> >>>> [ 0.000000][ T0] cma: pageblock_order not yet initialized. Called >>>> during early boot? >>> Good that we added those debug prints ;) >>> >>> I think I know what went wrong, as part of this arch,mm consolidation >>> patch series [1], I think the order of initialization is changed. >>> >>> With this patch the new order is ... >>> start_kernel() >>> - setup_arch() >>> - xxx_cma_reserve(); >>> - mm_core_init_early() >>> - free_area_init() >>> - sparse_init() >>> - set_pageblock_order() // this sets the pageblock_order. >>> >>> Whereas earlier set_pageblock_order() was called from initmem_init(), >>> just before cma reservations were being made. >>> >>> start_kernel() >>> - setup_arch() >>> - initmem_init() >>> - sparse_init() >>> - set_pageblock_order(); // this sets the pageblock_order >>> - xxx_cma_reserve(); >>> >>> So that means, pageblock_order is not initialized before these cma >>> reservation function calls, hence we are seeing these failures. >>> >>> setup_arch() { >>> ... >>> >>> /* >>> * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM and >>> * hugetlb. These must be called after initmem_init(), so that >>> * pageblock_order is initialised. >>> */ >>> fadump_cma_init(); >>> kdump_cma_reserve(); >>> kvm_cma_reserve(); >>> >>> ... >>> } >>> >>> >>> So what if we do.. >>> >>> start_kernel() { >>> ... >>> setup_arch(&command_line); >>> mm_core_init_early(); >>> setup_arch_post_mm_core_init(); // and here we call CMA reservation functions ? >> >> Unless I'm missing something these cma reservations can be moved to >> arch_mm_preinit(). >> It runs after mm_core_init_early() and before memblock moves the free >> memory to the buddy. >> > Right. I think, we should be able to use that... > > @Sourabh, > > I don't have access to the systems (travelling back...). Could you > please give this a try? > > > diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c > index cb5b73adc250..b1761909c23f 100644 > --- a/arch/powerpc/kernel/setup-common.c > +++ b/arch/powerpc/kernel/setup-common.c > @@ -35,7 +35,6 @@ > #include <linux/of_irq.h> > #include <linux/hugetlb.h> > #include <linux/pgtable.h> > -#include <asm/kexec.h> > #include <asm/io.h> > #include <asm/paca.h> > #include <asm/processor.h> > @@ -995,15 +994,6 @@ void __init setup_arch(char **cmdline_p) > > initmem_init(); > > - /* > - * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM and > - * hugetlb. These must be called after initmem_init(), so that > - * pageblock_order is initialised. > - */ > - fadump_cma_init(); > - kdump_cma_reserve(); > - kvm_cma_reserve(); > - > early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); > > if (ppc_md.setup_arch) > diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c > index 29bf347f6012..5ba947e4fe37 100644 > --- a/arch/powerpc/mm/mem.c > +++ b/arch/powerpc/mm/mem.c > @@ -30,6 +30,10 @@ > #include <asm/setup.h> > #include <asm/fixmap.h> > > +#include <asm/fadump.h> > +#include <asm/kexec.h> > +#include <asm/kvm_ppc.h> > + > #include <mm/mmu_decl.h> > > unsigned long long memory_limit __initdata; > @@ -268,6 +272,16 @@ void __init paging_init(void) > > void __init arch_mm_preinit(void) > { > + > + /* > + * Reserve large chunks of memory for use by CMA for kdump, fadump, KVM > + * and hugetlb. These must be called after pageblock_order is > + * initialised. > + */ > + fadump_cma_init(); > + kdump_cma_reserve(); > + kvm_cma_reserve(); > + > /* > * book3s is limited to 16 page sizes due to encoding this in > * a 4-bit field for slices. The above changes fix the issue. CMA initialization now works for both kdump and fadump. Thanks for the fix. - Sourabh Jain ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: powerpc/fadump: CMA init is failing 2026-02-28 13:46 ` Sourabh Jain @ 2026-02-28 17:54 ` Ritesh Harjani 0 siblings, 0 replies; 6+ messages in thread From: Ritesh Harjani @ 2026-02-28 17:54 UTC (permalink / raw) To: Sourabh Jain, Mike Rapoport Cc: Madhavan Srinivasan, linuxppc-dev, Michael Ellerman, Donet Tom, Hari Bathini, Mahesh J Salgaonkar, linux-mm Sourabh Jain <sourabhjain@linux.ibm.com> writes: > > The above changes fix the issue. CMA initialization now works for both > kdump and fadump. > Thanks Mike & Sourabh. I will soon share the fix. -ritesh ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2026-02-28 17:56 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2026-02-27 15:19 powerpc/fadump: CMA init is failing Sourabh Jain 2026-02-27 17:09 ` Ritesh Harjani 2026-02-27 20:50 ` Mike Rapoport 2026-02-28 2:35 ` Ritesh Harjani 2026-02-28 13:46 ` Sourabh Jain 2026-02-28 17:54 ` Ritesh Harjani
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