Re: [PATCH] x86: Construct 32 bit boot time page tables in nativeformat.

From: Mika Penttilä
Date: Sun Jan 20 2008 - 13:31:14 EST



+ * This is how much memory *in addition to the memory covered up to
+ * and including _end* we need mapped initially. We need one bit for
+ * each possible page, but only in low memory, which means
+ * 2^32/4096/8 = 128K worst case (4G/4G split.)
+ *
+ * Modulo rounding, each megabyte assigned here requires a kilobyte of
+ * memory, which is currently unreclaimed.
+ *
+ * This should be a multiple of a page.
+ */
+#define INIT_MAP_BEYOND_END (128*1024)
+
+/*

You have dropped the requirement to map all of low memory (the boot allocator is used for instance to construct physical mem mapping). Either you should fix your INIT_MAP_BEYOND_END or make a big comment telling us why it isn't necessary anymore to map low mem.

--Mika
--
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/