The shadow vmap for DEBUG_RODATA kernel text modification uses virt_to_page to get the pages from the pointer address and vmalloc_to_page for vmalloc'ed pages. - Changelog: Deal with read-only module text. Signed-off-by: Mathieu Desnoyers CC: Ingo Molnar --- arch/x86/kernel/alternative.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) Index: linux-2.6-lttng/arch/x86/kernel/alternative.c =================================================================== --- linux-2.6-lttng.orig/arch/x86/kernel/alternative.c 2008-03-24 10:00:30.000000000 -0400 +++ linux-2.6-lttng/arch/x86/kernel/alternative.c 2008-03-24 10:18:19.000000000 -0400 @@ -507,22 +507,27 @@ void *__kprobes text_poke(void *addr, co unsigned long flags; char *vaddr; int nr_pages = 2; + struct page *pages[2]; BUG_ON(len > sizeof(long)); BUG_ON((((long)addr + len - 1) & ~(sizeof(long) - 1)) - ((long)addr & ~(sizeof(long) - 1))); - { - struct page *pages[2] = { virt_to_page(addr), - virt_to_page(addr + PAGE_SIZE) }; - if (!pages[1]) - nr_pages = 1; - vaddr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL); - WARN_ON(!vaddr); - local_irq_save(flags); - memcpy(&vaddr[(unsigned long)addr & ~PAGE_MASK], opcode, len); - local_irq_restore(flags); - vunmap(vaddr); + if (is_vmalloc_addr(addr)) { + pages[0] = vmalloc_to_page(addr); + pages[1] = vmalloc_to_page(addr + PAGE_SIZE); + } else { + pages[0] = virt_to_page(addr); + pages[1] = virt_to_page(addr + PAGE_SIZE); } + BUG_ON(!pages[0]); + if (!pages[1]) + nr_pages = 1; + vaddr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL); + BUG_ON(!vaddr); + local_irq_save(flags); + memcpy(&vaddr[(unsigned long)addr & ~PAGE_MASK], opcode, len); + local_irq_restore(flags); + vunmap(vaddr); sync_core(); /* Could also do a CLFLUSH here to speed up CPU recovery; but that causes hangs on some VIA CPUs. */ -- Mathieu Desnoyers Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 -- 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/