Re: [PATCH v7 2/4] arm64: kdump: reserve crashkenel above 4G for crash dump kernel

From: John Donnelly
Date: Wed Mar 11 2020 - 22:39:49 EST

Next message: Roman Gushchin: "Re: [PATCH] mm,page_alloc,cma: conditionally prefer cma pageblocks for movable allocations"
Previous message: lishan: "Re: [PATCH] ocfs2: fix a null pointer derefrence in ocfs2_block_group_clear_bits()"
In reply to: Prabhakar Kushwaha: "Re: [PATCH v7 2/4] arm64: kdump: reserve crashkenel above 4G for crash dump kernel"
Next in thread: Prabhakar Kushwaha: "Re: [PATCH v7 2/4] arm64: kdump: reserve crashkenel above 4G for crash dump kernel"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

Hi Pk,

> On Mar 11, 2020, at 8:54 PM, Prabhakar Kushwaha <prabhakar.pkin@xxxxxxxxx> wrote:
>
> Dear John,
>
> On 3/11/2020 10:16 PM, John Donnelly wrote:
>> Hi
>>
>>
>>> On Mar 10, 2020, at 9:42 PM, Prabhakar Kushwaha <prabhakar.pkin@xxxxxxxxx> wrote:
>>>
>>> Dear John,
>>>
>>>
>>> On Tue, Mar 10, 2020 at 11:25 PM John Donnelly
>>> <john.p.donnelly@xxxxxxxxxx> wrote:
>>>>
>>>>
>>>>
>>>>> On Mar 10, 2020, at 12:34 PM, John Donnelly <John.P.Donnelly@xxxxxxxxxx> wrote:
>>>>>
>>>>> On 3/10/20 12:04 PM, Prabhakar Kushwaha wrote:
>>>>>> On 3/9/2020 11:53 PM, John Donnelly wrote:
>>>>>>> On 3/9/20 10:51 AM, Prabhakar Kushwaha wrote:
>>>>>>>> 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
>>>>>>>
>>>>>>> Hi,
>>>>>>>
>>>>>>> My mistake . I thought you were trying to allocate crashkernel AT 4G.
>>>>>>>
>>>>>>> That would be :
>>>>>>>
>>>>>>> crashkernel=1024M@4G
>>>>>>>
>>>>>>>
>>>>>>> But you are also allocating an additional 250M low too ?
>>>>>>>
>>>>>>> In your example
>>>>>>>
>>>>>>> crashkernel=1G - that is asking for 1024M in low memory.
>>>>>>>
>>>>>>> That likely won't work - from your own memory map there is no free
>>>>>>> segment that size :
>>>>>>>
>>>>>>>> 802f0000-8030ffff : reserved
>>>>>>>> e6247000-e6247fff : reserved
>>>>>>>> e6720000-e690ffff : reserved
>>>>>>>> e6a90000-e6a9ffff : reserved
>>>>>>>> e6ab0000-e721ffff : reserved
>>>>>>>> e7240000-e7240fff : reserved
>>>>>>>> fac00000-fafdffff : reserved
>>>>>>>
>>>>>>> The maximum size I've been able to use is 800M in the low 4GB range
>>>>>>> using a 5.4.17 kernel.
>>>>>>>
>>>>>> I am confused. I was following "[PATCH v7 4/4] kdump: update
>>>>>> Documentation about crashkernel on arm64"
>>>>>> + On arm64, use "crashkernel=Y[@X]". Note that the start address of
>>>>>> the kernel, X if explicitly specified, must be aligned to 2MiB
>>>>>> (0x200000).
>>>>>> + If crashkernel=Z,low is specified simultaneously, reserve spcified size
>>>>>> + low memory for crash kdump kernel devices firstly and then reserve
>>>>>> memory
>>>>>> + above 4G.
>>>>>> here is my understanding, if i pass crashkernel=1G crashkernel=250M,low
>>>>>> in bootargs.
>>>>>> - Linux will allocate first 250M in low memory (< 4G mem range)
>>>>>> - Than rest 850M will be allocate from above 4G memory.
>>>>>> So, parameters passed by me is correct and memory should be allocated.
>>>>>> please help me if my understanding is wrong.
>>>>>> --pk
>>>>>
>>>>> Hi
>>>>>
>>>>> Have you built a 5.5 kernel with these v4 patches applied ?
>>>>>
>>>>> These changes are not in a release yet.
>>>>>
>>>>
>>>>
>>>> I meant with v7 patches ;-). You also need a corresponding kexec CLI with fixes in it .
>>>>
>>>
>>> Yes, I have applied v7 patches to 5.6-rc4.
>>> After using kexec-tools() patches[1] on kexec-tools 2.0.20.git, It is
>>> working now. Logs are below. Thanks!!
>>>
>>>
>>> $ dmesg | grep crash
>>> [ 0.000000] Reserving 500MB of low memory at 3182MB for crashkernel
>>> (System low RAM: 2029MB)
>>> [ 0.000000] crashkernel reserved: 0x000000be98c00000 -
>>> 0x000000bf98c00000 (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
>>> crashkernel=500M,low nowatchdog earlycon module_blacklist=qed,qede
>>> [ 29.322393] crashkernel=500M,low
>>>
>>>
>>
>>
>> When you set crashkernel=4G , it automatically picked a range above 4GB ?
>>
>> I was under the impression it attempts to use < 4GB .
>>
>>
>
> this is strange, i even tried with 4G, 100M low.
>
> from logs looks like it is allocating 4G + 100M memory for crashkernel.
> Not like first 200M from < 4G and rest > 4G address region.
>
>
> 2$ dmesg | grep crash
> [ 0.000000] Reserving 100MB of low memory at 3866MB for crashkernel
> (System low RAM: 2029MB)
> [ 0.000000] crashkernel reserved: 0x000000be98c00000 -
> 0x000000bf98c00000 (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
> crashkernel=100M,low nowatchdog earlycon module_blacklist=qed,qede
> [ 29.314977] crashkernel=100M,low
> root@ubuntu-saber2$
>
>
> f1a00000-f7dfffff : reserved
> f1a00000-f7dfffff : Crash kernel (low)
>
> 9ffd000000-bffcffffff : System RAM
> be18000000-be97ffffff : reserved
> be98c00000-bf98bfffff : Crash kernel
>
> /proc/iomem also allocating space at 2 locations with tolal 4G
>
>
> What is the actual behavior. Also can you please share your log
>
> --pk
>

I donât have immediate access to a machine right now , but I will follow up in a couple of days.

Next message: Roman Gushchin: "Re: [PATCH] mm,page_alloc,cma: conditionally prefer cma pageblocks for movable allocations"
Previous message: lishan: "Re: [PATCH] ocfs2: fix a null pointer derefrence in ocfs2_block_group_clear_bits()"
In reply to: Prabhakar Kushwaha: "Re: [PATCH v7 2/4] arm64: kdump: reserve crashkenel above 4G for crash dump kernel"
Next in thread: Prabhakar Kushwaha: "Re: [PATCH v7 2/4] arm64: kdump: reserve crashkenel above 4G for crash dump kernel"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]