Messages in this thread Patch in this message | | | Date | Sat, 22 Jan 2011 03:12:26 +0100 | From | Andrea Arcangeli <> | Subject | [PATCH] thp: fix PARAVIRT x86 32bit noPAE |
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I reproduced your 32bit x86 problem with an initramfs with a hugepage benchmark placed as /init inside KVM (not exactly an extensive test but it was trivial to reproduce). I tested below fix with HIGHMEM4G and HIGHMEM64G with PARAVIRT=y (and verified setting PARAVIRT=n fixed it, in other email Minchan also verified that setting HIGHMEM64G=y also fixed it, to confirm my theory the problem was the below #ifdef).
The stress test reaches exit() successfully now (before the fix it crashed in out_of_memory() instead of do_exit as expected):
NMI watchdog disabled for cpu0: unable to create perf event: -2 �Kernel panic - not syncing: Attempted to kill init! Pid: 1, comm: init Not tainted 2.6.37+ #17 Call Trace: [<c14351d2>] ? panic+0x57/0x161 [<c107439b>] ? trace_hardirqs_on+0xb/0x10 [<c1045321>] ? do_exit+0x6b1/0x6e0 [<c10728ab>] ? trace_hardirqs_off+0xb/0x10 [<c1045389>] ? do_group_exit+0x39/0xa0 [<c1045403>] ? sys_exit_group+0x13/0x20 [<c1002d9c>] ? sysenter_do_call+0x12/0x3c QEMU 0.12.1 monitor - type 'help' for more information (qemu) quit
==== Subject: thp: fix PARAVIRT x86 32bit noPAE
From: Andrea Arcangeli <aarcange@redhat.com>
This fixes TRANSPARENT_HUGEPAGE=y with PARAVIRT=y and HIGHMEM64=n.
The #ifdef that this patch removes was erratically introduced to fix a build error for noPAE (where pmd.pmd doesn't exist). So then the kernel built but it failed at runtime because set_pmd_at was a noop. This will correct it by enabling set_pmd_at for noPAE mode too.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> ---
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 2071a8b..ebbc4d8 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -558,13 +558,12 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd) { -#if PAGETABLE_LEVELS >= 3 if (sizeof(pmdval_t) > sizeof(long)) /* 5 arg words */ pv_mmu_ops.set_pmd_at(mm, addr, pmdp, pmd); else - PVOP_VCALL4(pv_mmu_ops.set_pmd_at, mm, addr, pmdp, pmd.pmd); -#endif + PVOP_VCALL4(pv_mmu_ops.set_pmd_at, mm, addr, pmdp, + native_pmd_val(pmd)); } #endif -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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