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    SubjectRe: bug: kernel 3.0-rc3 not relocatable on i386?
    Hi Petr,

    Op 15-06-11 10:12, Petr Tesarik schreef:
    > Hi all,
    >
    > it seems that the 3.0-rc3 kernel is not relocatable on i386. I get
    > warnings about jiffies being an absolute symbol, and indeed, when GRUB
    > loads the kernel at a non-default address, jiffies is not relocated.
    >
    > In my example the kernel is configured with
    > CONFIG_PHYSICAL_START=0x1000000
    > CONFIG_PHYSICAL_ALIGN=0x200000
    > CONFIG_RELOCATABLE=y
    > and loaded at 0x200000 by GRUB.
    >
    > Booting fails when checking whether the timer works, because do_timer()
    > increments jiffies_64, but timer_irq_works() checks jiffies. The code
    > looks like this:
    >
    > c13daab7: 8b 3d 40 7a 39 c1 mov 0xc1397a40,%edi
    >
    > but arch/x86/boot/compressed/vmlinux.relocs does not contain c13daaba.
    > Consequently, timer_irq_works() reads the wrong memory location and
    > fails, causing a panic:
    >
    > kernel panic: IO-APIC + timer doesn't work! Boot with apic=debug and
    > send a report. Then try booting with the 'noapic' option.
    >
    > Needless to say, the kernel freezes a few initcalls later when booted
    > with noapic, because IO-APIC worked fine, in fact. I verified that by
    > inserting a debugging printk() in do_timer(), and I also verified with
    > that printk() that the address of jiffies_64 and the address of jiffies
    > differ at run time.

    Can you try this patch?

    diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
    index 89aed99..49e666e 100644
    --- a/arch/x86/kernel/vmlinux.lds.S
    +++ b/arch/x86/kernel/vmlinux.lds.S
    @@ -34,12 +34,11 @@ OUTPUT_FORMAT(CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT)
    #ifdef CONFIG_X86_32
    OUTPUT_ARCH(i386)
    ENTRY(phys_startup_32)
    -jiffies = jiffies_64;
    #else
    OUTPUT_ARCH(i386:x86-64)
    ENTRY(phys_startup_64)
    -jiffies_64 = jiffies;
    #endif
    +jiffies_64 = jiffies;

    #if defined(CONFIG_X86_64) && defined(CONFIG_DEBUG_RODATA)
    /*

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