diff options
authorAnton Wöllert <>2005-07-27 04:45:17 -0300
committerLinus Torvalds <>2005-07-27 16:34:34 -0700
commitbf85fa6c878aa3968df47d7f70a2b506c3e53b99 (patch)
parent59904159c316f7bc02d00ff7b0dc3f9d3afd07fd (diff)
[PATCH] ppc32: 8xx avoid icbi misbehaviour in __flush_dcache_icache_phys
On 8xx, in the case where a pagefault happens for a process who's not the owner of the vma in question (ptrace for instance), the flush operation is performed via the physical address. Unfortunately, that results in a strange, unexplainable "icbi" instruction fault, most likely due to a CPU bug (see oops below). Avoid that by flushing the page via its kernel virtual address. Oops: kernel access of bad area, sig: 11 [#2] NIP: C000543C LR: C000B060 SP: C0F35DF0 REGS: c0f35d40 TRAP: 0300 Not tainted MSR: 00009022 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 10 DAR: 00000010, DSISR: C2000000 TASK = c0ea8430[761] 'gdbserver' THREAD: c0f34000 Last syscall: 26 GPR00: 00009022 C0F35DF0 C0EA8430 00F59000 00000100 FFFFFFFF 00F58000 00000001 GPR08: C021DAEF C0270000 00009032 C0270000 22044024 10025428 01000800 00000001 GPR16: 007FFF3F 00000001 00000000 7FBC6AC0 00F61022 00000001 C0839300 C01E0000 GPR24: 00CD0889 C082F568 3000AC18 C02A7A00 C0EA15C8 00F588A9 C02ACB00 C02ACB00 NIP [c000543c] __flush_dcache_icache_phys+0x38/0x54 LR [c000b060] flush_dcache_icache_page+0x20/0x30 Call trace: [c000b154] update_mmu_cache+0x7c/0xa4 [c005ae98] do_wp_page+0x460/0x5ec [c005c8a0] handle_mm_fault+0x7cc/0x91c [c005ccec] get_user_pages+0x2fc/0x65c [c0027104] access_process_vm+0x9c/0x1d4 [c00076e0] sys_ptrace+0x240/0x4a4 [c0002bd0] ret_from_syscall+0x0/0x44 Signed-off-by: Marcelo Tosatti <> Signed-off-by: Linus Torvalds <>
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/ppc/mm/init.c b/arch/ppc/mm/init.c
index 6164a2b34733..33ada72c7330 100644
--- a/arch/ppc/mm/init.c
+++ b/arch/ppc/mm/init.c
@@ -562,6 +562,9 @@ void flush_dcache_icache_page(struct page *page)
+#elif CONFIG_8xx
+ /* On 8xx there is no need to kmap since highmem is not supported */
+ __flush_dcache_icache(page_address(page));
__flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);