> On Dec 18, 2019, at 8:56 PM, Chen Zhou <chenzhou10@xxxxxxxxxx> wrote: > > Hi John, > > On 2019/12/19 1:18, John Donnelly wrote: >> HI >> >> SEE INLINE ON A QUESTION : >> >>> On Dec 17, 2019, at 8:07 PM, Chen Zhou <chenzhou10@xxxxxxxxxx> wrote: >>> >>> Hi all, >>> >>> Friendly ping... >>> >>> On 2019/8/30 15:11, Chen Zhou wrote: >>>> I am busy with other things, so it was a long time before this version was >>>> released. >>>> >>>> This patch series enable reserving crashkernel above 4G in arm64. >>>> >>>> There are following issues in arm64 kdump: >>>> 1. We use crashkernel=X to reserve crashkernel below 4G, which will fail >>>> when there is no enough low memory. >>>> 2. Currently, crashkernel=Y@X can be used to reserve crashkernel above 4G, >>>> in this case, if swiotlb or DMA buffers are requierd, crash dump kernel >>>> will boot failure because there is no low memory available for allocation. >> >> >> Can you elaborate when the boot failures may fail due to lacking swiotlb or DMA buffers ? Are these related to certain adapters or specific platforms ? >> >> I have not seen this when using crashkernel=2024M@35GB . >> > > For example, in my environment "Huawei TaiShan 2280", > we need to use mpt3sas driver in crash dump kernel for dumping vmcore. > > mpt3sas driver needs to call dma_pool_alloc to allocate some pages, > if there is no DMA buffer, page allocation will fail, which leads to crash dump kernel boot failure, > like this: > > [2019/12/19 9:12:41] [ 12.403501] mpt3sas_cm0: diag reset: SUCCESS > [2019/12/19 9:12:41] [ 12.456076] mpt3sas_cm0: reply_post_free pool: dma_pool_alloc failed > [2019/12/19 9:12:41] [ 12.462515] pci 0004:48:00.0: can't derive routing for PCI INT A > [2019/12/19 9:12:41] [ 12.468761] mpt3sas 0004:49:00.0: PCI INT A: no GSI > [2019/12/19 9:12:41] [ 12.476348] mpt3sas_cm0: failure at drivers/scsi/mpt3sas/mpt3sas_scsih.c:10626/_scsih_probe()! > [2019/12/19 9:14:38] [ TIME ] Timed out waiting for device dev-di…b3\x2d890a\x2d2ead7df26f48.device. > [2019/12/19 9:14:38] [DEPEND] Dependency failed for Initrd Root Device. > [2019/12/19 9:14:38] [DEPEND] Dependency failed for /sysroot. > [2019/12/19 9:14:38] [DEPEND] Dependency failed for Initrd Root File System. > [2019/12/19 9:14:38] [DEPEND] Dependency failed for Reload Configuration from the Real Root. > [2019/12/19 9:14:38] [DEPEND] Dependency failed for File System C…40bae-9eb8-46b3-890a-2ead7df26f48. Thank you for sharing . We are not seeing this issue on a 5.4.0.rc8 ; Like I said in a previous email we can take crash dumps using crashkernel=768M for a “ standard “ small VMcore to local storage : 0004:01:00.0 RAID bus controller: Broadcom / LSI MegaRAID SAS-3 3316 [Intruder] (rev 01) Subsystem: Broadcom / LSI MegaRAID SAS 9361-16i Kernel driver in use: megaraid_sas What version of the kernel are you using ? > > Thanks, > Chen Zhou > >> >>>> >>>> To solve these issues, introduce crashkernel=X,low to reserve specified >>>> size low memory. >>>> Crashkernel=X tries to reserve memory for the crash dump kernel under >>>> 4G. If crashkernel=Y,low is specified simultaneously, reserve spcified >>>> size low memory for crash kdump kernel devices firstly and then reserve >>>> memory above 4G. >>>> >>>> When crashkernel is reserved above 4G in memory, that is, crashkernel=X,low >>>> is specified simultaneously, kernel should reserve specified size low memory >>>> for crash dump kernel devices. So there may be two crash kernel regions, one >>>> is below 4G, the other is above 4G. >>>> In order to distinct from the high region and make no effect to the use of >>>> kexec-tools, rename the low region as "Crash kernel (low)", and add DT property >>>> "linux,low-memory-range" to crash dump kernel's dtb to pass the low region. >>>> >>>> Besides, we need to modify kexec-tools: >>>> arm64: kdump: add another DT property to crash dump kernel's dtb(see [1]) >>>> >>>> The previous changes and discussions can be retrieved from: >>>> >>>> Changes since [v5] >>>> - Move reserve_crashkernel_low() into kernel/crash_core.c. >>>> - Delete crashkernel=X,high. >>>> - Modify crashkernel=X,low. >>>> If crashkernel=X,low is specified simultaneously, reserve spcified size low >>>> memory for crash kdump kernel devices firstly and then reserve memory above 4G. >>>> In addition, rename crashk_low_res as "Crash kernel (low)" for arm64, and then >>>> pass to crash dump kernel by DT property "linux,low-memory-range". >>>> - Update Documentation/admin-guide/kdump/kdump.rst. >>>> >>>> Changes since [v4] >>>> - Reimplement memblock_cap_memory_ranges for multiple ranges by Mike. >>>> >>>> Changes since [v3] >>>> - Add memblock_cap_memory_ranges back for multiple ranges. >>>> - Fix some compiling warnings. >>>> >>>> Changes since [v2] >>>> - Split patch "arm64: kdump: support reserving crashkernel above 4G" as >>>> two. Put "move reserve_crashkernel_low() into kexec_core.c" in a separate >>>> patch. >>>> >>>> Changes since [v1]: >>>> - Move common reserve_crashkernel_low() code into kernel/kexec_core.c. >>>> - Remove memblock_cap_memory_ranges() i added in v1 and implement that >>>> in fdt_enforce_memory_region(). >>>> There are at most two crash kernel regions, for two crash kernel regions >>>> case, we cap the memory range [min(regs[*].start), max(regs[*].end)] >>>> and then remove the memory range in the middle. >>>> >>>> [1]: https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.infradead.org_pipermail_kexec_2019-2DAugust_023569.html&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=t2fPg9D87F7D8jm0_3CG9yoiIKdRg4qc_thBw4bzMhc&m=ZAC6UYbT-3qLR3Dvevd09m6neWWzGWSphuvXXlXow68&s=9tn9kUBabiuYhVtXauANSDGaISnCnHLYcAUQgsPBFxs&e= >>>> [v1]: https://urldefense.proofpoint.com/v2/url?u=https-3A__lkml.org_lkml_2019_4_2_1174&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=t2fPg9D87F7D8jm0_3CG9yoiIKdRg4qc_thBw4bzMhc&m=ZAC6UYbT-3qLR3Dvevd09m6neWWzGWSphuvXXlXow68&s=F-lM7II2cuMF_sK3b6-QhSbWM3X-pI_WZEs0sZitS7A&e= >>>> [v2]: https://urldefense.proofpoint.com/v2/url?u=https-3A__lkml.org_lkml_2019_4_9_86&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=t2fPg9D87F7D8jm0_3CG9yoiIKdRg4qc_thBw4bzMhc&m=ZAC6UYbT-3qLR3Dvevd09m6neWWzGWSphuvXXlXow68&s=5Y-S6sqMTklHkOQsNtjTX3C7pV05BjKLGhJVfMHEvDs&e= >>>> [v3]: https://urldefense.proofpoint.com/v2/url?u=https-3A__lkml.org_lkml_2019_4_9_306&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=t2fPg9D87F7D8jm0_3CG9yoiIKdRg4qc_thBw4bzMhc&m=ZAC6UYbT-3qLR3Dvevd09m6neWWzGWSphuvXXlXow68&s=cWn4zSRQupaZ3jjz4eDvD-pNkoLyL_hsZoRx4yJoD0c&e= >>>> [v4]: https://urldefense.proofpoint.com/v2/url?u=https-3A__lkml.org_lkml_2019_4_15_273&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=t2fPg9D87F7D8jm0_3CG9yoiIKdRg4qc_thBw4bzMhc&m=ZAC6UYbT-3qLR3Dvevd09m6neWWzGWSphuvXXlXow68&s=Nslk4RJKIyIuT0IoQoolXNjupEDXplPhQQwnTSoXNWE&e= >>>> [v5]: https://urldefense.proofpoint.com/v2/url?u=https-3A__lkml.org_lkml_2019_5_6_1360&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=t2fPg9D87F7D8jm0_3CG9yoiIKdRg4qc_thBw4bzMhc&m=ZAC6UYbT-3qLR3Dvevd09m6neWWzGWSphuvXXlXow68&s=HJVAM6sCxV2DnNg5d4pw8WPqtkmQnKvztEmkSIgtQ5M&e= >>>> >>>> Chen Zhou (4): >>>> x86: kdump: move reserve_crashkernel_low() into crash_core.c >>>> arm64: kdump: reserve crashkenel above 4G for crash dump kernel >>>> arm64: kdump: add memory for devices by DT property, low-memory-range >>>> kdump: update Documentation about crashkernel on arm64 >>>> >>>> Documentation/admin-guide/kdump/kdump.rst | 13 ++++- >>>> Documentation/admin-guide/kernel-parameters.txt | 12 ++++- >>>> arch/arm64/include/asm/kexec.h | 3 ++ >>>> arch/arm64/kernel/setup.c | 8 ++- >>>> arch/arm64/mm/init.c | 61 +++++++++++++++++++++-- >>>> arch/x86/include/asm/kexec.h | 3 ++ >>>> arch/x86/kernel/setup.c | 65 +++---------------------- >>>> include/linux/crash_core.h | 4 ++ >>>> include/linux/kexec.h | 1 - >>>> kernel/crash_core.c | 65 +++++++++++++++++++++++++ >>>> 10 files changed, 168 insertions(+), 67 deletions(-) >>>> >>> >>> >>> _______________________________________________ >>> kexec mailing list >>> kexec@xxxxxxxxxxxxxxxxxxx >>> https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.infradead.org_mailman_listinfo_kexec&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=t2fPg9D87F7D8jm0_3CG9yoiIKdRg4qc_thBw4bzMhc&m=ZAC6UYbT-3qLR3Dvevd09m6neWWzGWSphuvXXlXow68&s=XMcFx61B_QPg-FUfG_-t88DKCnGm4grqu6zRguiHYrU&e= >> >> >> . _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
