kernel.git/arch/ppc/mm, branch linux-2.6.20.y

[PATCH] mm: use symbolic names instead of indices for zone initialisation

2006-10-11T18:14:14Z

Arch-independent zone-sizing is using indices instead of symbolic names to offset within an array related to zones (max_zone_pfns). The unintended impact is that ZONE_DMA and ZONE_NORMAL is initialised on powerpc instead of ZONE_DMA and ZONE_HIGHMEM when CONFIG_HIGHMEM is set. As a result, the the machine fails to boot but will boot with CONFIG_HIGHMEM turned off. The following patch properly initialises the max_zone_pfns[] array and uses symbolic names instead of indices in each architecture using arch-independent zone-sizing. Two users have successfully booted their powerpcs with it (one an ibook G4). It has also been boot tested on x86, x86_64, ppc64 and ia64. Please merge for 2.6.19-rc2. Credit to Benjamin Herrenschmidt for identifying the bug and rolling the first fix. Additional credit to Johannes Berg and Andreas Schwab for reporting the problem and testing on powerpc. Signed-off-by: Mel Gorman Cc: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] pidspace: is_init()

2006-09-29T16:18:12Z

This is an updated version of Eric Biederman's is_init() patch. (http://lkml.org/lkml/2006/2/6/280). It applies cleanly to 2.6.18-rc3 and replaces a few more instances of ->pid == 1 with is_init(). Further, is_init() checks pid and thus removes dependency on Eric's other patches for now. Eric's original description: There are a lot of places in the kernel where we test for init because we give it special properties. Most significantly init must not die. This results in code all over the kernel test ->pid == 1. Introduce is_init to capture this case. With multiple pid spaces for all of the cases affected we are looking for only the first process on the system, not some other process that has pid == 1. Signed-off-by: Eric W. Biederman Signed-off-by: Sukadev Bhattiprolu Cc: Dave Hansen Cc: Serge Hallyn Cc: Cedric Le Goater Cc: Acked-by: Paul Mackerras Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] make PROT_WRITE imply PROT_READ

2006-09-29T16:18:05Z

Make PROT_WRITE imply PROT_READ for a number of architectures which don't support write only in hardware. While looking at this, I noticed that some architectures which do not support write only mappings already take the exact same approach. For example, in arch/alpha/mm/fault.c: " if (cause < 0) { if (!(vma->vm_flags & VM_EXEC)) goto bad_area; } else if (!cause) { /* Allow reads even for write-only mappings */ if (!(vma->vm_flags & (VM_READ | VM_WRITE))) goto bad_area; } else { if (!(vma->vm_flags & VM_WRITE)) goto bad_area; } " Thus, this patch brings other architectures which do not support write only mappings in-line and consistent with the rest. I've verified the patch on ia64, x86_64 and x86. Additional discussion: Several architectures, including x86, can not support write-only mappings. The pte for x86 reserves a single bit for protection and its two states are read only or read/write. Thus, write only is not supported in h/w. Currently, if i 'mmap' a page write-only, the first read attempt on that page creates a page fault and will SEGV. That check is enforced in arch/blah/mm/fault.c. However, if i first write that page it will fault in and the pte will be set to read/write. Thus, any subsequent reads to the page will succeed. It is this inconsistency in behavior that this patch is attempting to address. Furthermore, if the page is swapped out, and then brought back the first read will also cause a SEGV. Thus, any arbitrary read on a page can potentially result in a SEGV. According to the SuSv3 spec, "if the application requests only PROT_WRITE, the implementation may also allow read access." Also as mentioned, some archtectures, such as alpha, shown above already take the approach that i am suggesting. The counter-argument to this raised by Arjan, is that the kernel is enforcing the write only mapping the best it can given the h/w limitations. This is true, however Alan Cox, and myself would argue that the inconsitency in behavior, that is applications can sometimes work/sometimes fails is highly undesireable. If you read through the thread, i think people, came to an agreement on the last patch i posted, as nobody has objected to it... Signed-off-by: Jason Baron Cc: Russell King Cc: "Luck, Tony" Cc: Hugh Dickins Cc: Roman Zippel Cc: Geert Uytterhoeven Cc: Paul Mackerras Cc: Benjamin Herrenschmidt Acked-by: Andi Kleen Acked-by: Alan Cox Cc: Arjan van de Ven Acked-by: Paul Mundt Cc: Kazumoto Kojima Cc: Ian Molton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Have Power use add_active_range() and free_area_init_nodes()

2006-09-27T15:26:11Z

Size zones and holes in an architecture independent manner for Power. [judith@osdl.org: build fix] Signed-off-by: Mel Gorman Cc: Dave Hansen Cc: Andy Whitcroft Cc: Andi Kleen Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: "Keith Mannthey" Cc: "Luck, Tony" Cc: KAMEZAWA Hiroyuki Cc: Yasunori Goto Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Remove obsolete #include

2006-06-30T17:25:36Z

Signed-off-by: Jörn Engel Signed-off-by: Adrian Bunk

powerpc: Fix some missed ppc32 mm->context.id conversions

2006-06-13T03:43:00Z

Signed-off-by: Paul Mackerras

powerpc: add context.vdso_base for 32-bit too

2006-06-11T04:15:17Z

This adds a vdso_base element to the mm_context_t for 32-bit compiles (both for ARCH=powerpc and ARCH=ppc). This fixes the compile errors that have been reported in arch/powerpc/kernel/signal_32.c. Signed-off-by: Paul Mackerras

[PATCH] lock PTE before updating it in 440/BookE page fault handler

2006-03-29T02:44:15Z

Fix 44x and BookE page fault handler to correctly lock PTE before trying to pte_update() it, otherwise this PTE might be swapped out after pte_present() check but before pte_uptdate() call, resulting in corrupted PTE. This can happen with enabled preemption and low memory condition. Signed-off-by: Eugene Surovegin Signed-off-by: Paul Mackerras

ppc: Remove CHRP, POWER3 and POWER4 support from arch/ppc

2006-03-27T23:22:10Z

32-bit CHRP machines are now supported only in arch/powerpc, as are all 64-bit PowerPC processors. This means that we don't use Open Firmware on any platform in arch/ppc any more. This makes PReP support a single-platform option like every other platform support option in arch/ppc now, thus CONFIG_PPC_MULTIPLATFORM is gone from arch/ppc. CONFIG_PPC_PREP is the option that selects PReP support and is generally what has replaced CONFIG_PPC_MULTIPLATFORM within arch/ppc. _machine is all but dead now, being #defined to 0. Updated Makefiles, comments and Kconfig options generally to reflect these changes. Signed-off-by: Paul Mackerras

Merge git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc

2006-03-23T06:20:46Z

* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (78 commits) [PATCH] powerpc: Add FSL SEC node to documentation [PATCH] macintosh: tidy-up driver_register() return values [PATCH] powerpc: tidy-up of_register_driver()/driver_register() return values [PATCH] powerpc: via-pmu warning fix [PATCH] macintosh: cleanup the use of i2c headers [PATCH] powerpc: dont allow old RTC to be selected [PATCH] powerpc: make powerbook_sleep_grackle static [PATCH] powerpc: Fix warning in add_memory [PATCH] powerpc: update mailing list addresses [PATCH] powerpc: Remove calculation of io hole [PATCH] powerpc: iseries: Add bootargs to /chosen [PATCH] powerpc: iseries: Add /system-id, /model and /compatible [PATCH] powerpc: Add strne2a() to convert a string from EBCDIC to ASCII [PATCH] powerpc: iseries: Make more stuff static in platforms/iseries/mf.c [PATCH] powerpc: iseries: Remove pointless iSeries_(restart|power_off|halt) [PATCH] powerpc: iseries: mf related cleanups [PATCH] powerpc: Replace platform_is_lpar() with a firmware feature [PATCH] powerpc: trivial: Cleanup whitespace in cputable.h [PATCH] powerpc: Remove unused iommu_off logic from pSeries_init_early() [PATCH] powerpc: Unconfuse htab_bolt_mapping() callers ...