Re: [PATCH] [ppc] Do not reserve cpu spin-table for crash kernel

["Suzuki K. Poulose" <suzuki@in.ibm.com>]

On 06/25/2012 04:47 PM, Suzuki K. Poulose wrote:
> Simon,
>

Ping.

Suzuki

> Please let me know your response.
>
> Thanks
> Suzuki
>
> On 06/18/2012 11:57 AM, Suzuki K. Poulose wrote:
>> On 05/24/2012 11:39 AM, Suzuki K. Poulose wrote:
>>> As of now, the kexec reserves the spin-table for all the CPUs
>>> on an SMP machine. The spin-table is pointed to by the
>>> cpu-release-addr property in the device-tree. Reserving the
>>> spin-table in the crash kernel will cause a BUG(), if the table
>>> lies outside the memory reserved for the crashkernel.
>>>
>>> Disable reserving the spin-table regions and use maxcpus=1 to
>>> use only the crashing CPU to boot the crash kernel.
>>>
>>> Signed-off-by: Suzuki K. Poulose<suzuki@in.ibm.com>
>>
>> Simon,
>>
>> Any response on this one ?
>>
>> I have tested this on a Currituck board (476, SMP) with a UP kernel.
>> Without this patch, the secondary kernel hits 'PANIC' in boot while
>> trying to reserve a memory(the spin table), outside the memory
>> range(crash reserve).
>>
>>
>> Thanks
>> Suzuki
>>
>>> ---
>>>
>>> kexec/arch/ppc/crashdump-powerpc.c | 19 +++++++++++++------
>>> kexec/arch/ppc/fixup_dtb.c | 4 ++++
>>> 2 files changed, 17 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/kexec/arch/ppc/crashdump-powerpc.c
>>> b/kexec/arch/ppc/crashdump-powerpc.c
>>> index 1bef69b..4c8c75d 100644
>>> --- a/kexec/arch/ppc/crashdump-powerpc.c
>>> +++ b/kexec/arch/ppc/crashdump-powerpc.c
>>> @@ -262,10 +262,19 @@ static void ulltoa(unsigned long long i, char
>>> *str)
>>> }
>>> }
>>>
>>> +/* Append str to cmdline */
>>> +static void add_cmdline(char *cmdline, char *str)
>>> +{
>>> + int cmdlen = strlen(cmdline) + strlen(str);
>>> + if (cmdlen> (COMMAND_LINE_SIZE - 1))
>>> + die("Command line overflow\n");
>>> + strcat(cmdline, str);
>>> +}
>>> +
>>> static int add_cmdline_param(char *cmdline, unsigned long long addr,
>>> char *cmdstr, char *byte)
>>> {
>>> - int cmdlen, len, align = 1024;
>>> + int align = 1024;
>>> char str[COMMAND_LINE_SIZE], *ptr;
>>>
>>> /* Passing in =xxxK / =xxxM format. Saves space required in cmdline.*/
>>> @@ -284,11 +293,8 @@ static int add_cmdline_param(char *cmdline,
>>> unsigned long long addr,
>>> ptr += strlen(str);
>>> ulltoa(addr, ptr);
>>> strcat(str, byte);
>>> - len = strlen(str);
>>> - cmdlen = strlen(cmdline) + len;
>>> - if (cmdlen> (COMMAND_LINE_SIZE - 1))
>>> - die("Command line overflow\n");
>>> - strcat(cmdline, str);
>>> +
>>> + add_cmdline(cmdline, str);
>>>
>>> dbgprintf("Command line after adding elfcorehdr: %s\n", cmdline);
>>>
>>> @@ -365,6 +371,7 @@ int load_crashdump_segments(struct kexec_info
>>> *info, char *mod_cmdline,
>>> */
>>> add_cmdline_param(mod_cmdline, elfcorehdr, " elfcorehdr=", "K");
>>> add_cmdline_param(mod_cmdline, saved_max_mem, " savemaxmem=", "M");
>>> + add_cmdline(mod_cmdline, " maxcpus=1");
>>> return 0;
>>> }
>>>
>>> diff --git a/kexec/arch/ppc/fixup_dtb.c b/kexec/arch/ppc/fixup_dtb.c
>>> index e9890a4..f832026 100644
>>> --- a/kexec/arch/ppc/fixup_dtb.c
>>> +++ b/kexec/arch/ppc/fixup_dtb.c
>>> @@ -172,6 +172,9 @@ static void fixup_reserve_regions(struct
>>> kexec_info *info, char *blob_buf)
>>> }
>>> }
>>>
>>> +#if 0
>>> + /* XXX: Do not reserve spin-table for CPUs. */
>>> +
>>> /* Add reserve regions for cpu-release-addr */
>>> nodeoffset = fdt_node_offset_by_prop_value(blob_buf, -1,
>>> "device_type", "cpu", 4);
>>> while (nodeoffset != -FDT_ERR_NOTFOUND) {
>>> @@ -201,6 +204,7 @@ static void fixup_reserve_regions(struct
>>> kexec_info *info, char *blob_buf)
>>> nodeoffset = fdt_node_offset_by_prop_value(blob_buf, nodeoffset,
>>> "device_type", "cpu", 4);
>>> }
>>> +#endif
>>>
>>> out:
>>> print_fdt_reserve_regions(blob_buf);
>>>
>>>
>>> _______________________________________________
>>> kexec mailing list
>>> kexec@lists.infradead.org
>>> http://lists.infradead.org/mailman/listinfo/kexec
>>>
>>
>>
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>
>
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