On 3/9/2020 10:18 AM, Prabhakar Kushwaha wrote: > Hi Chen, > > On Sat, Mar 7, 2020 at 4:36 PM Chen Zhou <chenzhou10@xxxxxxxxxx> wrote: >> >> >> >> On 2020/3/5 18:13, Prabhakar Kushwaha wrote: >>> On Mon, Dec 23, 2019 at 8:57 PM Chen Zhou <chenzhou10@xxxxxxxxxx> wrote: >>>> >>>> Crashkernel=X tries to reserve memory for the crash dump kernel under >>>> 4G. If crashkernel=X,low is specified simultaneously, reserve spcified >>>> size low memory for crash kdump kernel devices firstly and then reserve >>>> memory above 4G. >>>> >>>> Signed-off-by: Chen Zhou <chenzhou10@xxxxxxxxxx> >>>> --- >>>> arch/arm64/kernel/setup.c | 8 +++++++- >>>> arch/arm64/mm/init.c | 31 +++++++++++++++++++++++++++++-- >>>> 2 files changed, 36 insertions(+), 3 deletions(-) >>>> >>>> diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c >>>> index 56f6645..04d1c87 100644 >>>> --- a/arch/arm64/kernel/setup.c >>>> +++ b/arch/arm64/kernel/setup.c >>>> @@ -238,7 +238,13 @@ static void __init request_standard_resources(void) >>>> kernel_data.end <= res->end) >>>> request_resource(res, &kernel_data); >>>> #ifdef CONFIG_KEXEC_CORE >>>> - /* Userspace will find "Crash kernel" region in /proc/iomem. */ >>>> + /* >>>> + * Userspace will find "Crash kernel" region in /proc/iomem. >>>> + * Note: the low region is renamed as Crash kernel (low). >>>> + */ >>>> + if (crashk_low_res.end && crashk_low_res.start >= res->start && >>>> + crashk_low_res.end <= res->end) >>>> + request_resource(res, &crashk_low_res); >>>> if (crashk_res.end && crashk_res.start >= res->start && >>>> crashk_res.end <= res->end) >>>> request_resource(res, &crashk_res); >>>> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c >>>> index b65dffd..0d7afd5 100644 >>>> --- a/arch/arm64/mm/init.c >>>> +++ b/arch/arm64/mm/init.c >>>> @@ -80,6 +80,7 @@ static void __init reserve_crashkernel(void) >>>> { >>>> unsigned long long crash_base, crash_size; >>>> int ret; >>>> + phys_addr_t crash_max = arm64_dma32_phys_limit; >>>> >>>> ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), >>>> &crash_size, &crash_base); >>>> @@ -87,12 +88,38 @@ static void __init reserve_crashkernel(void) >>>> if (ret || !crash_size) >>>> return; >>>> >>>> + ret = reserve_crashkernel_low(); >>>> + if (!ret && crashk_low_res.end) { >>>> + /* >>>> + * If crashkernel=X,low specified, there may be two regions, >>>> + * we need to make some changes as follows: >>>> + * >>>> + * 1. rename the low region as "Crash kernel (low)" >>>> + * In order to distinct from the high region and make no effect >>>> + * to the use of existing kexec-tools, rename the low region as >>>> + * "Crash kernel (low)". >>>> + * >>>> + * 2. change the upper bound for crash memory >>>> + * Set MEMBLOCK_ALLOC_ACCESSIBLE upper bound for crash memory. >>>> + * >>>> + * 3. mark the low region as "nomap" >>>> + * The low region is intended to be used for crash dump kernel >>>> + * devices, just mark the low region as "nomap" simply. >>>> + */ >>>> + const char *rename = "Crash kernel (low)"; >>>> + >>>> + crashk_low_res.name = rename; >>>> + crash_max = MEMBLOCK_ALLOC_ACCESSIBLE; >>>> + memblock_mark_nomap(crashk_low_res.start, >>>> + resource_size(&crashk_low_res)); >>>> + } >>>> + >>>> crash_size = PAGE_ALIGN(crash_size); >>>> >>>> if (crash_base == 0) { >>>> /* Current arm64 boot protocol requires 2MB alignment */ >>>> - crash_base = memblock_find_in_range(0, arm64_dma32_phys_limit, >>>> - crash_size, SZ_2M); >>>> + crash_base = memblock_find_in_range(0, crash_max, crash_size, >>>> + SZ_2M); >>>> if (crash_base == 0) { >>>> pr_warn("cannot allocate crashkernel (size:0x%llx)\n", >>>> crash_size); >>>> -- >>> >>> I tested this patch series on ARM64-ThunderX2 with no issue with >>> bootargs crashkenel=X@Y crashkernel=250M,low >>> >>> $ dmesg | grep crash >>> [ 0.000000] crashkernel reserved: 0x0000000b81200000 - >>> 0x0000000c81200000 (4096 MB) >>> [ 0.000000] Kernel command line: >>> BOOT_IMAGE=/boot/vmlinuz-5.6.0-rc4+ >>> root=UUID=866b8df3-14f4-4e11-95a1-74a90ee9b694 ro >>> crashkernel=4G@0xb81200000 crashkernel=250M,low nowatchdog earlycon >>> [ 29.310209] crashkernel=250M,low >>> >>> $ kexec -p -i /boot/vmlinuz-`uname -r` >>> --initrd=/boot/initrd.img-`uname -r` --reuse-cmdline >>> $ echo 1 > /proc/sys/kernel/sysrq ; echo c > /proc/sysrq-trigger >>> >>> But when i tried with crashkernel=4G crashkernel=250M,low as bootargs. >>> Kernel is not able to allocate memory. >>> [ 0.000000] cannot allocate crashkernel (size:0x100000000) >>> [ 0.000000] Kernel command line: >>> BOOT_IMAGE=/boot/vmlinuz-5.6.0-rc4+ >>> root=UUID=866b8df3-14f4-4e11-95a1-74a90ee9b694 ro crashkernel=4G >>> crashkernel=250M,low nowatchdog >>> [ 29.332081] crashkernel=250M,low >>> >>> does crashkernel=X@Y mandatory to get allocated beyond 4G? >>> am I missing something? >> >> I can't reproduce the problem in my environment, can you test with other size, >> such as "crashkernel=1G crashkernel=250M,low", see if there is the same issue. >> > I tried 1G also. Same error, please find the logs > > $ dmesg | grep crash > [ 0.000000] cannot allocate crashkernel (size:0x40000000) > [ 0.000000] Kernel command line: > BOOT_IMAGE=/boot/vmlinuz-5.6.0-rc4+ > root=UUID=866b8df3-14f4-4e11-95a1-74a90ee9b694 ro nowatchdog earlycon > crashkernel=1G crashkernel=250M,low > [ 29.326916] crashkernel=250M,low > > >> Besides, crashkernel=X@Y isn't mandatory to get allocated beyond 4G, > > this was my understanding also. > >> can you show the whole file /proc/iomem. >> > > $ cat /proc/iomem > 00000000-00000000 : PCI ECAM > 00000000-00000000 : PCI ECAM > 00000000-00000000 : PCI Bus 0000:00 > 00000000-00000000 : PCI Bus 0000:0f > 00000000-00000000 : PCI Bus 0000:10 > 00000000-00000000 : 0000:10:00.0 > 00000000-00000000 : 0000:10:00.0 > 00000000-00000000 : PCI Bus 0000:01 > 00000000-00000000 : 0000:01:00.0 > 00000000-00000000 : 0000:01:00.1 > 00000000-00000000 : PCI Bus 0000:05 > 00000000-00000000 : 0000:05:00.0 > 00000000-00000000 : 0000:05:00.1 > 00000000-00000000 : PCI Bus 0000:09 > 00000000-00000000 : 0000:09:00.0 > 00000000-00000000 : 0000:09:00.1 > 00000000-00000000 : 0000:00:10.0 > 00000000-00000000 : ahci > 00000000-00000000 : 0000:00:10.1 > 00000000-00000000 : ahci > 00000000-00000000 : PCI Bus 0000:80 > 00000000-00000000 : PCI Bus 0000:83 > 00000000-00000000 : 0000:83:00.0 > 00000000-00000000 : 0000:83:00.0 > 00000000-00000000 : nvme > 00000000-00000000 : PCI Bus 0000:89 > 00000000-00000000 : 0000:89:00.0 > 00000000-00000000 : e1000e > 00000000-00000000 : 0000:89:00.0 > 00000000-00000000 : 0000:89:00.0 > 00000000-00000000 : e1000e > 00000000-00000000 : 0000:89:00.0 > 00000000-00000000 : e1000e > 00000000-00000000 : PCI Bus 0000:8d > 00000000-00000000 : 0000:8d:00.0 > 00000000-00000000 : 0000:8d:00.0 > 00000000-00000000 : mpt3sas > 00000000-00000000 : reserved > 00000000-00000000 : System RAM > 00000000-00000000 : Kernel code > 00000000-00000000 : reserved > 00000000-00000000 : Kernel data > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : System RAM > 00000000-00000000 : reserved > 00000000-00000000 : System RAM > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : System RAM > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : System RAM > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : System RAM > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : System RAM > 00000000-00000000 : reserved > 00000000-00000000 : CAV901C:00 > 00000000-00000000 : CAV901D:00 > 00000000-00000000 : CAV901C:00 > 00000000-00000000 : CAV901E:00 > 00000000-00000000 : CAV901C:00 > 00000000-00000000 : CAV901F:00 > 00000000-00000000 : CAV901C:00 > 00000000-00000000 : CAV9006:00 > 00000000-00000000 : CAV9006:00 > 00000000-00000000 : ARMH0011:00 > 00000000-00000000 : ARMH0011:00 > 00000000-00000000 : arm-smmu-v3.0.auto > 00000000-00000000 : arm-smmu-v3.0.auto > 00000000-00000000 : arm-smmu-v3.1.auto > 00000000-00000000 : arm-smmu-v3.1.auto > 00000000-00000000 : arm-smmu-v3.2.auto > 00000000-00000000 : arm-smmu-v3.2.auto > 00000000-00000000 : CAV901C:01 > 00000000-00000000 : CAV901D:01 > 00000000-00000000 : CAV901C:01 > 00000000-00000000 : CAV901E:01 > 00000000-00000000 : CAV901C:01 > 00000000-00000000 : CAV901F:01 > 00000000-00000000 : CAV901C:01 > 00000000-00000000 : CAV9007:06 > 00000000-00000000 : CAV9007:06 > 00000000-00000000 : arm-smmu-v3.3.auto > 00000000-00000000 : arm-smmu-v3.3.auto > 00000000-00000000 : arm-smmu-v3.4.auto > 00000000-00000000 : arm-smmu-v3.4.auto > 00000000-00000000 : arm-smmu-v3.5.auto > 00000000-00000000 : arm-smmu-v3.5.auto > 00000000-00000000 : System RAM > 00000000-00000000 : System RAM > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : System RAM > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : reserved > 00000000-00000000 : PCI Bus 0000:00 > 00000000-00000000 : PCI Bus 0000:01 > 00000000-00000000 : 0000:01:00.0 > 00000000-00000000 : 0000:01:00.1 > 00000000-00000000 : 0000:01:00.0 > 00000000-00000000 : 0000:01:00.1 > 00000000-00000000 : 0000:01:00.0 > 00000000-00000000 : 0000:01:00.1 > 00000000-00000000 : PCI Bus 0000:05 > 00000000-00000000 : 0000:05:00.0 > 00000000-00000000 : bnx2x > 00000000-00000000 : 0000:05:00.1 > 00000000-00000000 : bnx2x > 00000000-00000000 : 0000:05:00.0 > 00000000-00000000 : bnx2x > 00000000-00000000 : 0000:05:00.0 > 00000000-00000000 : bnx2x > 00000000-00000000 : 0000:05:00.1 > 00000000-00000000 : bnx2x > 00000000-00000000 : 0000:05:00.1 > 00000000-00000000 : bnx2x > 00000000-00000000 : PCI Bus 0000:09 > 00000000-00000000 : 0000:09:00.0 > 00000000-00000000 : i40e > 00000000-00000000 : 0000:09:00.1 > 00000000-00000000 : i40e > 00000000-00000000 : 0000:09:00.0 > 00000000-00000000 : 0000:09:00.1 > 00000000-00000000 : 0000:09:00.0 > 00000000-00000000 : i40e > 00000000-00000000 : 0000:09:00.1 > 00000000-00000000 : i40e > 00000000-00000000 : 0000:09:00.0 > 00000000-00000000 : 0000:09:00.1 > 00000000-00000000 : 0000:00:0f.0 > 00000000-00000000 : xhci-hcd > 00000000-00000000 : 0000:00:0f.0 > 00000000-00000000 : 0000:00:0f.1 > 00000000-00000000 : xhci-hcd > 00000000-00000000 : 0000:00:0f.1 > 00000000-00000000 : 0000:00:10.0 > 00000000-00000000 : ahci > 00000000-00000000 : 0000:00:10.1 > 00000000-00000000 : ahci > 00000000-00000000 : PCI Bus 0000:80 > resending with correct logs (after login as root) $ cat /proc/iomem 30000000-37ffffff : PCI ECAM 38000000-3fffffff : PCI ECAM 40000000-5fffffff : PCI Bus 0000:00 40000000-417fffff : PCI Bus 0000:0f 40000000-417fffff : PCI Bus 0000:10 40000000-40ffffff : 0000:10:00.0 41000000-4101ffff : 0000:10:00.0 41800000-418fffff : PCI Bus 0000:01 41800000-4183ffff : 0000:01:00.0 41840000-4187ffff : 0000:01:00.1 41900000-419fffff : PCI Bus 0000:05 41900000-4197ffff : 0000:05:00.0 41980000-419fffff : 0000:05:00.1 41a00000-41afffff : PCI Bus 0000:09 41a00000-41a7ffff : 0000:09:00.0 41a80000-41afffff : 0000:09:00.1 41b00000-41b0ffff : 0000:00:10.0 41b00000-41b0ffff : ahci 41b10000-41b1ffff : 0000:00:10.1 41b10000-41b1ffff : ahci 60000000-7fffffff : PCI Bus 0000:80 60000000-600fffff : PCI Bus 0000:83 60000000-6001ffff : 0000:83:00.0 60020000-60023fff : 0000:83:00.0 60020000-60023fff : nvme 60100000-601fffff : PCI Bus 0000:89 60100000-6017ffff : 0000:89:00.0 60100000-6017ffff : e1000e 60180000-601bffff : 0000:89:00.0 601c0000-601dffff : 0000:89:00.0 601c0000-601dffff : e1000e 601e0000-601e3fff : 0000:89:00.0 601e0000-601e3fff : e1000e 60200000-603fffff : PCI Bus 0000:8d 60200000-602fffff : 0000:8d:00.0 60300000-6030ffff : 0000:8d:00.0 60300000-6030ffff : mpt3sas 802f0000-8030ffff : reserved e6247000-e6247fff : reserved e6720000-e690ffff : reserved e6a90000-e6a9ffff : reserved e6ab0000-e721ffff : reserved e7240000-e7240fff : reserved fac00000-fafdffff : reserved 400040400-40004041f : CAV901C:00 400040480-400040567 : CAV901D:00 400040480-400040567 : CAV901C:00 400040600-40004073b : CAV901E:00 400040600-40004073b : CAV901C:00 400041400-40004177f : CAV901F:00 400041400-40004177f : CAV901C:00 402000100-402000fff : CAV9006:00 402000100-402000fff : CAV9006:00 402020000-40202ffff : ARMH0011:00 402020000-40202ffff : ARMH0011:00 402300000-40230ffff : arm-smmu-v3.0.auto 402300000-40230ffff : arm-smmu-v3.0.auto 402320000-40232ffff : arm-smmu-v3.1.auto 402320000-40232ffff : arm-smmu-v3.1.auto 402340000-40234ffff : arm-smmu-v3.2.auto 402340000-40234ffff : arm-smmu-v3.2.auto 440040400-44004041f : CAV901C:01 440040480-440040567 : CAV901D:01 440040480-440040567 : CAV901C:01 440040600-44004073b : CAV901E:01 440040600-44004073b : CAV901C:01 440041400-44004177f : CAV901F:01 440041400-44004177f : CAV901C:01 4421a0000-4421affff : CAV9007:06 4421a0000-4421affff : CAV9007:06 442300000-44230ffff : arm-smmu-v3.3.auto 442300000-44230ffff : arm-smmu-v3.3.auto 442320000-44232ffff : arm-smmu-v3.4.auto 442320000-44232ffff : arm-smmu-v3.4.auto 442340000-44234ffff : arm-smmu-v3.5.auto 442340000-44234ffff : arm-smmu-v3.5.auto b81200000-c811fffff : System RAM b81280000-b8270ffff : Kernel code b82710000-b82dfffff : reserved b82e00000-b83168fff : Kernel data b83169000-baccd7fff : reserved c78a00000-c7fffffff : reserved c80129000-c801a9fff : reserved c801aa000-c809e9fff : reserved c809ec000-c809eefff : reserved c809ef000-c811fffff : reserved 10000000000-13fffffffff : PCI Bus 0000:00 10000000000-100013fffff : PCI Bus 0000:01 10000000000-100007fffff : 0000:01:00.0 10000800000-10000ffffff : 0000:01:00.1 10001000000-1000101ffff : 0000:01:00.0 10001020000-1000103ffff : 0000:01:00.1 10001040000-1000104ffff : 0000:01:00.0 10001050000-1000105ffff : 0000:01:00.1 10001400000-100037fffff : PCI Bus 0000:05 10001400000-1000140ffff : 0000:05:00.0 10001400000-1000140ffff : bnx2x 10001410000-1000141ffff : 0000:05:00.1 10001410000-1000141ffff : bnx2x 10001800000-10001ffffff : 0000:05:00.0 10001800000-10001ffffff : bnx2x 10002000000-100027fffff : 0000:05:00.0 10002000000-100027fffff : bnx2x 10002800000-10002ffffff : 0000:05:00.1 10002800000-10002ffffff : bnx2x 10003000000-100037fffff : 0000:05:00.1 10003000000-100037fffff : bnx2x 10003800000-100053fffff : PCI Bus 0000:09 10003800000-10003ffffff : 0000:09:00.0 10003800000-10003ffffff : i40e 10004000000-100047fffff : 0000:09:00.1 10004000000-100047fffff : i40e 10004800000-10004bfffff : 0000:09:00.0 10004c00000-10004ffffff : 0000:09:00.1 10005000000-10005007fff : 0000:09:00.0 10005000000-10005007fff : i40e 10005008000-1000500ffff : 0000:09:00.1 10005008000-1000500ffff : i40e 10005010000-1000510ffff : 0000:09:00.0 10005110000-1000520ffff : 0000:09:00.1 10005400000-1000540ffff : 0000:00:0f.0 10005400000-1000540ffff : xhci-hcd 10005410000-1000541ffff : 0000:00:0f.0 10005420000-1000542ffff : 0000:00:0f.1 10005420000-1000542ffff : xhci-hcd 10005430000-1000543ffff : 0000:00:0f.1 10005440000-1000544ffff : 0000:00:10.0 10005440000-1000544ffff : ahci 10005450000-1000545ffff : 0000:00:10.1 10005450000-1000545ffff : ahci 14000000000-17fffffffff : PCI Bus 0000:80 failure with crashkernel=1G :~$ dmesg | grep crash [ 0.000000] cannot allocate crashkernel (size:0x40000000) [ 0.000000] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-5.6.0-rc4+ root=UUID=866b8df3-14f4-4e11-95a1-74a90ee9b694 ro nowatchdog earlycon crashkernel=1G crashkernel=250M,low [ 29.326916] crashkernel=250M,low --pk _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec