[PATCH] x86: Quark: Add comment on TLB flush to setup_arch

From: Bryan O'Donoghue
Date: Wed Sep 24 2014 - 16:26:13 EST

Quark X1000 requires CR3 to be rewritten to flush TLB entries
irrespective of the PGE bits in CR4 or PTE.PGE

Add a comment to setup_arch to indicate that the code


Will already have flushed the TLB @ the CR3 reload allowing us
to skip over a potential if/else for Quark

Signed-off-by: Bryan O'Donoghue <pure.logic@xxxxxxxxxxxxxxxxx>
arch/x86/kernel/setup.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 41ead8d..e7d7f6e 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -878,6 +878,11 @@ void __init setup_arch(char **cmdline_p)
initial_page_table + KERNEL_PGD_BOUNDARY,

+ /*
+ * Locate the page directory and flush the TLB.
+ * On Quark X1000 rewriting CR3 flushes the TLB no if/else is required
+ * to choose between __flush_tlb() and __flush_tlb_all()
+ */

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/