Hi, this patch set depends on the following patches posted earlier.
[PATCH V2 1/2] x86: add arch_pfn_possible helper lkml: Message-Id: <1408103043-31015-2-git-send-email-fhrb...@redhat.com> [PATCH V2 2/2] x86: add phys addr validity check for /dev/mem mmap lkml: Message-Id: <1408103043-31015-3-git-send-email-fhrb...@redhat.com> This is an attempt to remove the high_memory limit for the read/write access to /dev/mem. IMHO there is no reason for this limit on x86. It is presented in the generic valid_phys_addr_range, which is used only by (read|write)_mem. IIUIC it's main purpose is for the generic xlate_dev_mem_ptr, which is using only the direct kernel mapping __va translation. Since the valid_phys_addr_range is called as the first check in (read|write)_mem, it basically does not allow to access anything above high_memory on x86. The first patch adds high_memory check to x86's (xlate|unxlate)_dev_mem_ptr, so the direct kernel mapping can be safely used for system RAM bellow high_memory. This is IMHO the only valid reason to use high_memory check in (read|write)_mem. The second patch removes the high_memory check from valid_phys_addr_range, allowing read/write to access non-system RAM above high_memory. So far this was possible only by using mmap. I hope I haven't overlooked something. Many thanks Frantisek Hrbata (2): x86: add high_memory check to (xlate|unxlate)_dev_mem_ptr x86: remove high_memory check from valid_phys_addr_range arch/x86/mm/ioremap.c | 9 ++++++--- arch/x86/mm/mmap.c | 2 +- 2 files changed, 7 insertions(+), 4 deletions(-) -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
