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. 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
