Re: [PATCH 1/5] purgatory: put variables altered by kexec in .data not .bss

David Vrabel
2013-09-16T12:48:33Z

On 16/09/13 13:43, Daniel Kiper wrote:
> On Thu, Sep 12, 2013 at 09:00:38PM +0100, David Vrabel wrote:
>> From: David Vrabel <david.vrabel@citrix.com>
>>
>> elf_rel_set_symbol() fails if the symbol is in the .bss section.
>>
>> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
>> ---
>> purgatory/arch/i386/console-x86.c | 6 +++---
>> purgatory/arch/i386/crashdump_backup.c | 8 +++++---
>> purgatory/arch/x86_64/purgatory-x86_64.c | 6 +++---
>> purgatory/include/purgatory.h | 4 ++++
>> purgatory/purgatory.c | 4 ++--
>> 5 files changed, 17 insertions(+), 11 deletions(-)
>>
>> diff --git a/purgatory/arch/i386/console-x86.c b/purgatory/arch/i386/console-x86.c
>> index 9773573..40a734b 100644
>> --- a/purgatory/arch/i386/console-x86.c
>> +++ b/purgatory/arch/i386/console-x86.c
>> @@ -55,9 +55,9 @@ static void putchar_vga(int ch)
>> */
>>
>> /* Base Address */
>> -uint8_t console_serial = 0;
>> -uint16_t serial_base = 0x3f8; /* TTYS0 */
>> -uint32_t serial_baud = 0;
>> +uint8_t console_serial __data = 0;
>> +uint16_t serial_base __data = 0x3f8; /* TTYS0 */
>> +uint32_t serial_baud __data = 0;
>
> Hmmm... I do not know why we need this patch. I can build kexec-tools
> in my env without it. I suppose that most of people can too.
> Could you check what is wrong with your build system?

Regardless of whether it works with some tools, it doesn't make a whole
lot of sense to try and set the value of symbols in the .bss section.
.bss is only for symbols with a value of zero.

David