linux/arch/x86/mm
Suresh Siddha 1adcaafe74 x86, pat: Allow ISA memory range uncacheable mapping requests
Max Vozeler reported:
>  Bug 13877 -  bogl-term broken with CONFIG_X86_PAT=y, works with =n
>
>  strace of bogl-term:
>  814   mmap2(NULL, 65536, PROT_READ|PROT_WRITE, MAP_SHARED, 4, 0)
>				 = -1 EAGAIN (Resource temporarily unavailable)
>  814   write(2, "bogl: mmaping /dev/fb0: Resource temporarily unavailable\n",
>	       57) = 57

PAT code maps the ISA memory range as WB in the PAT attribute, so that
fixed range MTRR registers define the actual memory type (UC/WC/WT etc).

But the upper level is_new_memtype_allowed() API checks are failing,
as the request here is for UC and the return tracked type is WB (Tracked type is
WB as MTRR type for this legacy range potentially will be different for each
4k page).

Fix is_new_memtype_allowed() by always succeeding the ISA address range
checks, as the null PAT (WB) and def MTRR fixed range register settings
satisfy the memory type needs of the applications that map the ISA address
range.

Reported-and-Tested-by: Max Vozeler <xam@debian.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-17 14:12:44 -07:00
..
kmemcheck kmemcheck: add opcode self-testing at boot 2009-06-15 15:49:22 +02:00
dump_pagetables.c x86: remove (null) in /sys kernel_page_tables 2009-04-14 11:50:22 +02:00
extable.c x86: uaccess: introduce try and catch framework 2009-01-23 17:17:36 -08:00
fault.c x86: Remove spurious printk level from segfault message 2009-07-11 09:56:19 +02:00
gup.c Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-06-20 11:29:32 -07:00
highmem_32.c x86: Export kmap_atomic_prot() needed for TTM. 2009-07-29 15:56:22 +10:00
hugetlbpage.c x86: ignore VM_LOCKED when determining if hugetlb-backed page tables can be shared or not 2009-05-29 08:40:03 -07:00
init_32.c Merge commit 'linus/master' into HEAD 2009-06-15 15:50:49 +02:00
init_64.c x86: don't clear nodes_states[N_NORMAL_MEMORY] when numa is not compiled in 2009-07-08 10:32:50 -07:00
init.c x86: Declare check_efer() before it gets used 2009-07-01 16:52:54 +02:00
iomap_32.c Merge commit 'origin/master' into for-linus/xen/master 2009-04-07 13:34:16 -07:00
ioremap.c Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-17 09:56:11 -07:00
k8topology_64.c x86: k8 numa register active regions later 2009-01-06 13:21:21 +01:00
kmmio.c Merge branch 'linus' into tracing/core 2009-05-07 11:17:34 +02:00
Makefile kmemcheck: add the kmemcheck core 2009-06-13 15:37:30 +02:00
memtest.c x86: memtest: use pointers of equal type for comparison 2009-06-11 16:26:35 +02:00
mmap.c x86: update copyrights 2009-01-31 04:21:18 +01:00
mmio-mod.c tracing: x86, mmiotrace: only register for die notifier when tracer active 2009-04-29 11:33:34 +02:00
numa_32.c x86: mm/numa_32.c calculate_numa_remap_pages should use __init 2009-04-17 22:43:13 +02:00
numa_64.c x86, mm: Fix node_possible_map logic 2009-05-18 09:21:04 +02:00
numa.c cpumask: convert node_to_cpumask_map[] to cpumask_var_t 2009-03-13 14:35:31 +01:00
pageattr-test.c x86: make sure the CPA test code's use of _PAGE_UNUSED1 is obvious 2008-09-05 17:09:57 +02:00
pageattr.c x86: Fix CPA memtype reserving in the set_pages_array*() cases 2009-08-03 19:36:09 +02:00
pat.c x86, pat: Allow ISA memory range uncacheable mapping requests 2009-08-17 14:12:44 -07:00
pf_in.c x86: fix mmiotrace 8-bit register decoding 2008-10-14 10:33:50 +02:00
pf_in.h x86 mmiotrace: move files into arch/x86/mm/. 2008-05-24 11:25:37 +02:00
pgtable_32.c x86/32: no need to use set_pte_present in set_pte_vaddr 2009-03-19 14:04:18 +01:00
pgtable.c x86, 32-bit: Fix double accounting in reserve_top_address() 2009-08-04 16:27:29 +02:00
srat_32.c x86: Fix a typo in a printk message 2009-05-06 12:23:12 +02:00
srat_64.c x86-64: Fix bad_srat() to clear all state 2009-07-21 15:20:01 -07:00
testmmiotrace.c x86: add far read test to testmmiotrace 2009-03-02 10:20:35 +01:00
tlb.c x86: add x2apic_wrmsr_fence() to x2apic flush tlb paths 2009-03-18 09:36:14 +01:00