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* x86: convert to generic helpers for IPI function callsJens Axboe2008-06-26
| | | | | | | | | | This converts x86, x86-64, and xen to use the new helpers for smp_call_function() and friends, and adds support for smp_call_function_single(). Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Add generic helpers for arch IPI function callsJens Axboe2008-06-26
| | | | | | | | | | | | | | | | | This adds kernel/smp.c which contains helpers for IPI function calls. In addition to supporting the existing smp_call_function() in a more efficient manner, it also adds a more scalable variant called smp_call_function_single() for calling a given function on a single CPU only. The core of this is based on the x86-64 patch from Nick Piggin, lots of changes since then. "Alan D. Brunelle" <Alan.Brunelle@hp.com> has contributed lots of fixes and suggestions as well. Also thanks to Paul E. McKenney <paulmck@linux.vnet.ibm.com> for reviewing RCU usage and getting rid of the data allocation fallback deadlock. Acked-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Merge branch 'release' of ↵Linus Torvalds2008-06-24
|\ | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6: [IA64] Eliminate NULL test after alloc_bootmem in iosapic_alloc_rte() [IA64] Handle count==0 in sn2_ptc_proc_write() [IA64] Fix boot failure on ia64/sn2
| * [IA64] Eliminate NULL test after alloc_bootmem in iosapic_alloc_rte()Julia Lawall2008-06-24
| | | | | | | | | | | | | | | | | | As noted by Akinobu Mita alloc_bootmem and related functions never return NULL and always return a zeroed region of memory. Thus a NULL test or memset after calls to these functions is unnecessary. Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Tony Luck <tony.luck@intel.com>
| * [IA64] Handle count==0 in sn2_ptc_proc_write()Cliff Wickman2008-06-24
| | | | | | | | | | | | | | | | | | | | | | The fix applied in e0c6d97c65e0784aade7e97b9411f245a6c543e7 "security hole in sn2_ptc_proc_write" didn't take into account the case where count==0 (which results in a buffer underrun when adding the trailing '\0'). Thanks to Andi Kleen for pointing this out. Signed-off-by: Cliff Wickman <cpw@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
| * [IA64] Fix boot failure on ia64/sn2Jes Sorensen2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | | | Call check_sal_cache_flush() after platform_setup() as check_sal_cache_flush() now relies on being able to call platform vector code. Problem was introduced by: 3463a93def55c309f3c0d0a8aaf216be3be42d64 "Update check_sal_cache_flush to use platform_send_ipi()" Signed-off-by: Jes Sorensen <jes@sgi.com> Tested-by: Alex Chiang: <achiang@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
* | Merge branch 'kvm-updates-2.6.26' of ↵Linus Torvalds2008-06-24
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm * 'kvm-updates-2.6.26' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: KVM: Remove now unused structs from kvm_para.h x86: KVM guest: Use the paravirt clocksource structs and functions KVM: Make kvm host use the paravirt clocksource structs x86: Make xen use the paravirt clocksource structs and functions x86: Add structs and functions for paravirt clocksource KVM: VMX: Fix host msr corruption with preemption enabled KVM: ioapic: fix lost interrupt when changing a device's irq KVM: MMU: Fix oops on guest userspace access to guest pagetable KVM: MMU: large page update_pte issue with non-PAE 32-bit guests (resend) KVM: MMU: Fix rmap_write_protect() hugepage iteration bug KVM: close timer injection race window in __vcpu_run KVM: Fix race between timer migration and vcpu migration
| * | x86: KVM guest: Use the paravirt clocksource structs and functionsGerd Hoffmann2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates the kvm host code to use the pvclock structs and functions, thereby making it compatible with Xen. The patch also fixes an initialization bug: on SMP systems the per-cpu has two different locations early at boot and after CPU bringup. kvmclock must take that in account when registering the physical address within the host. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Make kvm host use the paravirt clocksource structsGerd Hoffmann2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | This patch updates the kvm host code to use the pvclock structs. It also makes the paravirt clock compatible with Xen. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | x86: Make xen use the paravirt clocksource structs and functionsGerd Hoffmann2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates the xen guest to use the pvclock structs and helper functions. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | x86: Add structs and functions for paravirt clocksourceGerd Hoffmann2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds structs for the paravirt clocksource ABI used by both xen and kvm (pvclock-abi.h). It also adds some helper functions to read system time and wall clock time from a paravirtual clocksource (pvclock.[ch]). They are based on the xen code. They are enabled using CONFIG_PARAVIRT_CLOCK. Subsequent patches of this series will put the code in use. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: VMX: Fix host msr corruption with preemption enabledAvi Kivity2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Switching msrs can occur either synchronously as a result of calls to the msr management functions (usually in response to the guest touching virtualized msrs), or asynchronously when preempting a kvm thread that has guest state loaded. If we're unlucky enough to have the two at the same time, host msrs are corrupted and the machine goes kaput on the next syscall. Most easily triggered by Windows Server 2008, as it does a lot of msr switching during bootup. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: MMU: Fix oops on guest userspace access to guest pagetableAvi Kivity2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KVM has a heuristic to unshadow guest pagetables when userspace accesses them, on the assumption that most guests do not allow userspace to access pagetables directly. Unfortunately, in addition to unshadowing the pagetables, it also oopses. This never triggers on ordinary guests since sane OSes will clear the pagetables before assigning them to userspace, which will trigger the flood heuristic, unshadowing the pagetables before the first userspace access. One particular guest, though (Xenner) will run the kernel in userspace, triggering the oops. Since the heuristic is incorrect in this case, we can simply remove it. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: MMU: large page update_pte issue with non-PAE 32-bit guests (resend)Marcelo Tosatti2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kvm_mmu_pte_write() does not handle 32-bit non-PAE large page backed guests properly. It will instantiate two 2MB sptes pointing to the same physical 2MB page when a guest large pte update is trapped. Instead of duplicating code to handle this, disallow directory level updates to happen through kvm_mmu_pte_write(), so the two 2MB sptes emulating one guest 4MB pte can be correctly created by the page fault handling path. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: MMU: Fix rmap_write_protect() hugepage iteration bugMarcelo Tosatti2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | rmap_next() does not work correctly after rmap_remove(), as it expects the rmap chains not to change during iteration. Fix (for now) by restarting iteration from the beginning. Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: close timer injection race window in __vcpu_runMarcelo Tosatti2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a timer fires after kvm_inject_pending_timer_irqs() but before local_irq_disable() the code will enter guest mode and only inject such timer interrupt the next time an unrelated event causes an exit. It would be simpler if the timer->pending irq conversion could be done with IRQ's disabled, so that the above problem cannot happen. For now introduce a new vcpu requests bit to cancel guest entry. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
| * | KVM: Fix race between timer migration and vcpu migrationMarcelo Tosatti2008-06-24
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | A guest vcpu instance can be scheduled to a different physical CPU between the test for KVM_REQ_MIGRATE_TIMER and local_irq_disable(). If that happens, the timer will only be migrated to the current pCPU on the next exit, meaning that guest LAPIC timer event can be delayed until a host interrupt is triggered. Fix it by cancelling guest entry if any vcpu request is pending. This has the side effect of nicely consolidating vcpu->requests checks. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
* | Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds2008-06-24
|\ \ | |/ |/| | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: xen: remove support for non-PAE 32-bit
| * xen: remove support for non-PAE 32-bitJeremy Fitzhardinge2008-06-24
| | | | | | | | | | | | | | | | | | | | | | | | Non-PAE operation has been deprecated in Xen for a while, and is rarely tested or used. xen-unstable has now officially dropped non-PAE support. Since Xen/pvops' non-PAE support has also been broken for a while, we may as well completely drop it altogether. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds2008-06-23
|\| | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: xen: don't drop NX bit xen: mask unwanted pte bits in __supported_pte_mask xen: Use wmb instead of rmb in xen_evtchn_do_upcall(). x86: fix NULL pointer deref in __switch_to
| * xen: don't drop NX bitJeremy Fitzhardinge2008-06-20
| | | | | | | | | | | | | | | | | | | | Because NX is now enforced properly, we must put the hypercall page into the .text segment so that it is executable. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Stable Kernel <stable@kernel.org> Cc: the arch/x86 maintainers <x86@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * xen: mask unwanted pte bits in __supported_pte_maskJeremy Fitzhardinge2008-06-20
| | | | | | | | | | | | | | | | | | | | [ Stable: this isn't a bugfix in itself, but it's a pre-requiste for "xen: don't drop NX bit" ] Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Stable Kernel <stable@kernel.org> Cc: the arch/x86 maintainers <x86@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'release' of ↵Linus Torvalds2008-06-20
|\ \ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6: [IA64] SN2: security hole in sn2_ptc_proc_write
| * | [IA64] SN2: security hole in sn2_ptc_proc_writeCliff Wickman2008-06-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | Security hole in sn2_ptc_proc_write It is possible to overrun a buffer with a write to this /proc file. Signed-off-by: Cliff Wickman <cpw@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
* | | alpha: resurrect Cypress IDE quirkIvan Kokshaysky2008-06-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Which was removed in the hope that generic legacy IDE quirk in drivers/pci/probe.c is sufficient for Cypress IDE. It isn't, as this controller has non-standard BAR layout: secondary channel registers are in the BAR0-1 of the second PCI function - not in the BAR2-3 of the same function, as the generic quirk routine assumes. Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | alpha: fix compile failures with gcc-4.3 (bug #10438)Ivan Kokshaysky2008-06-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Vast majority of these build failures are gcc-4.3 warnings about static functions and objects being referenced from non-static (read: "extern inline") functions, in conjunction with our -Werror. We cannot just convert "extern inline" to "static inline", as people keep suggesting all the time, because "extern inline" logic is crucial for generic kernel build. So - just make sure that all callees of critical "extern inline" functions are also "extern inline"; - use "static inline", wherever it's possible. traps.c: work around gcc-4.3 being too smart about array bounds-checking. TODO: add "gnu_inline" attribute to all our "extern inline" functions to ensure desired behaviour with future compilers. Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | alpha: link failure fixIvan Kokshaysky2008-06-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With built-in scsi disk driver, the final link fails with a following error: `.exit.text' referenced in section `.rodata' of drivers/built-in.o: defined in discarded section `.exit.text' of drivers/built-in.o This happens with -Os (CONFIG_CC_OPTIMIZE_FOR_SIZE=y) with all gcc-4 versions, and also with -O2 and gcc-4.3. The problem is in sd.c:sd_major() being inlined into __exit function exit_sd(), and the compiler generating a jump table in .rodata section for the 'switch' statement in sd_major(). So we have references to discarded section. Fixed with a big hammer in the form of -fno-jump-tables. Note that jump tables vs. discarded sections is a generic problem, other architectures are just lucky not to suffer from it. But with a slightly more complex switch/case statement it can be reproduced on x86 as well. So maybe at some point we should consider -fno-jump-tables as a generic compile option... Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds2008-06-20
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, geode: add a VSA2 ID for General Software x86: use BOOTMEM_EXCLUSIVE on 32-bit x86, 32-bit: fix boot failure on TSC-less processors x86: fix NULL pointer deref in __switch_to x86: set PAE PHYSICAL_MASK_SHIFT to 44 bits.
| * | x86, geode: add a VSA2 ID for General SoftwareJordan Crouse2008-06-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | General Software writes their own VSA2 module for their version of the Geode BIOS, which returns a different ID then the standard VSA2. This was causing the framebuffer driver to break for most GSW boards. Signed-off-by: Jordan Crouse <jordan.crouse@amd.com> Cc: tglx@linutronix.de Cc: linux-geode@lists.infradead.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | x86: use BOOTMEM_EXCLUSIVE on 32-bitBernhard Walle2008-06-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch uses the BOOTMEM_EXCLUSIVE for crashkernel reservation also for i386 and prints a error message on failure. The patch is still for 2.6.26 since it is only bug fixing. The unification of reserve_crashkernel() between i386 and x86_64 should be done for 2.6.27. Signed-off-by: Bernhard Walle <bwalle@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org>
| * | x86, 32-bit: fix boot failure on TSC-less processorsMikael Pettersson2008-06-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Booting 2.6.26-rc6 on my 486 DX/4 fails with a "BUG: Int 6" (invalid opcode) and a kernel halt immediately after the kernel has been uncompressed. The BUG shows EIP pointing to an rdtsc instruction in native_read_tsc(), invoked from native_sched_clock(). (This error occurs so early that not even the serial console can capture it.) A bisection showed that this bug first occurs in 2.6.26-rc3-git7, via commit 9ccc906c97e34fd91dc6aaf5b69b52d824386910: >x86: distangle user disabled TSC from unstable > >tsc_enabled is set to 0 from the command line switch "notsc" and from >the mark_tsc_unstable code. Seperate those functionalities and replace >tsc_enable with tsc_disable. This makes also the native_sched_clock() >decision when to use TSC understandable. > >Preparatory patch to solve the sched_clock() issue on 32 bit. > >Signed-off-by: Thomas Gleixner <tglx@linutronix.de> The core reason for this bug is that native_sched_clock() gets called before tsc_init(). Before the commit above, tsc_32.c used a "tsc_enabled" variable which defaulted to 0 == disabled, and which only got enabled late in tsc_init(). Thus early calls to native_sched_clock() would skip the TSC and use jiffies instead. After the commit above, tsc_32.c uses a "tsc_disabled" variable which defaults to 0, meaning that the TSC is Ok to use. Early calls to native_sched_clock() now erroneously try to use the TSC on !cpu_has_tsc processors, leading to invalid opcode exceptions. My proposed fix is to initialise tsc_disabled to a "soft disabled" state distinct from the hard disabled state set up by the "notsc" kernel option. This fixes the native_sched_clock() problem. It also allows tsc_init() to be simplified: instead of setting tsc_disabled = 1 on every error return, we just set tsc_disabled = 0 once when all checks have succeeded. I've verified that this lets my 486 boot again. I've also verified that a Core2 machine still uses the TSC as clocksource after the patch. Signed-off-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | x86: fix NULL pointer deref in __switch_toSuresh Siddha2008-06-19
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patrick McHardy reported a crash: > > I get this oops once a day, its apparently triggered by something > > run by cron, but the process is a different one each time. > > > > Kernel is -git from yesterday shortly before the -rc6 release > > (last commit is the usb-2.6 merge, the x86 patches are missing), > > .config is attached. > > > > I'll retry with current -git, but the patches that have gone in > > since I last updated don't look related. > > > > [62060.043009] BUG: unable to handle kernel NULL pointer dereference at > > 000001ff > > [62060.043009] IP: [<c0102a9b>] __switch_to+0x2f/0x118 > > [62060.043009] *pde = 00000000 > > [62060.043009] Oops: 0002 [#1] PREEMPT Vegard Nossum analyzed it: > This decodes to > > 0: 0f ae 00 fxsave (%eax) > > so it's related to the floating-point context. This is the exact > location of the crash: > > $ addr2line -e arch/x86/kernel/process_32.o -i ab0 > include/asm/i387.h:232 > include/asm/i387.h:262 > arch/x86/kernel/process_32.c:595 > > ...so it looks like prev_task->thread.xstate->fxsave has become NULL. > Or maybe it never had any other value. Somehow (as described below) TS_USEDFPU is set but the fpu is not allocated or freed. Another possible FPU pre-emption issue with the sleazy FPU optimization which was benign before but not so anymore, with the dynamic FPU allocation patch. New task is getting exec'd and it is prempted at the below point. flush_thread() { ... /* * Forget coprocessor state.. */ clear_fpu(tsk); <----- Preemption point clear_used_math(); ... } Now when it context switches in again, as the used_math() is still set and fpu_counter can be > 5, we will do a math_state_restore() which sets the task's TS_USEDFPU. After it continues from the above preemption point it does clear_used_math() and much later free_thread_xstate(). Now, at the next context switch, it is quite possible that xstate is null, used_math() is not set and TS_USEDFPU is still set. This will trigger unlazy_fpu() causing kernel oops. Fix this by clearing tsk's fpu_counter before clearing task's fpu. Reported-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* / Reinstate ZERO_PAGE optimization in 'get_user_pages()' and fix XIPLinus Torvalds2008-06-20
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KAMEZAWA Hiroyuki and Oleg Nesterov point out that since the commit 557ed1fa2620dc119adb86b34c614e152a629a80 ("remove ZERO_PAGE") removed the ZERO_PAGE from the VM mappings, any users of get_user_pages() will generally now populate the VM with real empty pages needlessly. We used to get the ZERO_PAGE when we did the "handle_mm_fault()", but since fault handling no longer uses ZERO_PAGE for new anonymous pages, we now need to handle that special case in follow_page() instead. In particular, the removal of ZERO_PAGE effectively removed the core file writing optimization where we would skip writing pages that had not been populated at all, and increased memory pressure a lot by allocating all those useless newly zeroed pages. This reinstates the optimization by making the unmapped PTE case the same as for a non-existent page table, which already did this correctly. While at it, this also fixes the XIP case for follow_page(), where the caller could not differentiate between the case of a page that simply could not be used (because it had no "struct page" associated with it) and a page that just wasn't mapped. We do that by simply returning an error pointer for pages that could not be turned into a "struct page *". The error is arbitrarily picked to be EFAULT, since that was what get_user_pages() already used for the equivalent IO-mapped page case. [ Also removed an impossible test for pte_offset_map_lock() failing: that's not how that function works ] Acked-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Nick Piggin <npiggin@suse.de> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [POWERPC] Clear sub-page HPTE present bits when demoting page sizePaul Mackerras2008-06-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | When we demote a slice from 64k to 4k, and we are about to insert an HPTE for a 4k subpage and we notice that there is an existing 64k HPTE, we first invalidate that HPTE before inserting the new 4k subpage HPTE. Since the bits that encode which hash bucket the old HPTE was in overlap with the bits that encode which of the 16 subpages have HPTEs, we need to clear out the subpage HPTE-present bits before starting to insert HPTEs for the 4k subpages. If we don't do that, we can erroneously think that a subpage already has an HPTE when it doesn't. That in itself wouldn't be such a problem except that when we go to update the HPTE that we think is present on machines with a hypervisor, the hypervisor can tell us that the HPTE we think is there is actually there even though it isn't, which can lead to a process getting stuck in a loop, continually faulting. The reason for the confusion is that the AVPN (abbreviated virtual page number) we are looking for in the HPTE for a 4k subpage can actually match the AVPN in a stale HPTE for another 64k page. For example, the HPTE for the 4k subpage at 0x84000f000 will be in the same hash bucket and have the same AVPN as the HPTE for the 64k page at 0x8400f0000. This fixes the code to clear out the subpage HPTE-present bits. Signed-off-by: Paul Mackerras <paulus@samba.org>
* [POWERPC] 4xx: Clear new TLB cache attribute bits in Data Storage vectorJosh Boyer2008-06-18
| | | | | | | | | | A recent commit added support for the new 440x6 and 464 cores that have the added WL1, IL1I, IL1D, IL2I, and ILD2 bits for the caching attributes in the TLBs. The new bits were cleared in the finish_tlb_load function, however a similar bit of code was missed in the DataStorage interrupt vector. Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
* x86-64: Fix "bytes left to copy" return value for copy_from_user()Linus Torvalds2008-06-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most users by far do not care about the exact return value (they only really care about whether the copy succeeded in its entirety or not), but a few special core routines actually care deeply about exactly how many bytes were copied from user space. And the unrolled versions of the x86-64 user copy routines would sometimes report that it had copied more bytes than it actually had. Very few uses actually have partial copies to begin with, but to make this bug even harder to trigger, most x86 CPU's use the "rep string" instructions for normal user copies, and that version didn't have this issue. To make it even harder to hit, the one user of this that really cared about the return value (and used the uncached version of the copy that doesn't use the "rep string" instructions) was the generic write routine, which pre-populated its source, once more hiding the problem by avoiding the exception case that triggers the bug. In other words, very special thanks to Bron Gondwana who not only triggered this, but created a test-program to show it, and bisected the behavior down to commit 08291429cfa6258c4cd95d8833beb40f828b194e ("mm: fix pagecache write deadlocks") which changed the access pattern just enough that you can now trigger it with 'writev()' with multiple iovec's. That commit itself was not the cause of the bug, it just allowed all the stars to align just right that you could trigger the problem. [ Side note: this is just the minimal fix to make the copy routines (with __copy_from_user_inatomic_nocache as the particular version that was involved in showing this) have the right return values. We really should improve on the exceptional case further - to make the copy do a byte-accurate copy up to the exact page limit that causes it to fail. As it is, the callers have to do extra work to handle the limit case gracefully. ] Reported-by: Bron Gondwana <brong@fastmail.fm> Cc: Nick Piggin <npiggin@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> (which didn't have this problem), and since most users that do the carethis was very hard to trigger, but
* Merge branch 'release' of ↵Linus Torvalds2008-06-16
|\ | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6: [IA64] Fix CONFIG_IA64_SGI_UV build error [IA64] Update check_sal_cache_flush to use platform_send_ipi() [IA64] perfmon: fix async exit bug
| * [IA64] Fix CONFIG_IA64_SGI_UV build errorJack Steiner2008-06-16
| | | | | | | | | | | | | | | | Fix build error in CONFIG_IA64_SGI_UV config. (GENERIC builds are ok). Signed-off-by: Jack Steiner <steiner@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
| * [IA64] Update check_sal_cache_flush to use platform_send_ipi()Alex Chiang2008-06-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | check_sal_cache_flush is used to detect broken firmware that drops pending interrupts. The old implementation schedules a timer interrupt for itself in the future by getting the current value of the Interval Timer Counter + 1000 cycles, waits for the interrupt to be pended, calls SAL_CACHE_FLUSH, and finally checks to see if the interrupt is still pending. This implementation can cause problems for virtual machine code if the process of scheduling the timer interrupt takes more than 1000 cycles; the virtual machine can end up sleeping for several hundred years while waiting for the ITC to wrap around. The fix is to use platform_send_ipi. The processor will still send an interrupt to itself, using the IA64_IPI_DM_INT delivery mode, which causes the IPI to look like an external interrupt. The rest of the SAL_CACHE_FLUSH + checking to see if the interrupt is still pending remains unchanged. This fix has been boot tested successfully on: - intel tiger2 - hp rx6600 - hp rx5670 The rx5670 has known buggy firmware, where SAL_CACHE_FLUSH drops pending interrupts. A boot test on this machine showed this message on the console: SAL: SAL_CACHE_FLUSH drops interrupts; PAL_CACHE_FLUSH will be used instead Which proves that the self-inflicted IPI approach is viable. And as expected, the other tested platforms correctly did not display the warning. Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
| * [IA64] perfmon: fix async exit bugstephane eranian2008-06-11
| | | | | | | | | | | | | | | | | | Move the cleanup of the async queue to the close callback from the flush callback. This avoids losing asynchronous overflow notifications when the file descriptor is shared by multiple processes and one terminates. Signed-off-by: Stephane Eranian <eranian@gmail.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
* | Merge branch 'merge' of ↵Linus Torvalds2008-06-16
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (21 commits) [POWERPC] Turn on ATA_SFF so we get SATA_SVW back in defconfigs [POWERPC] Remove ppc32's export of console_drivers [POWERPC] Fix -Os kernel builds with newer gcc versions [POWERPC] Fix bootwrapper builds with newer gcc versions [POWERPC] Build fix for drivers/macintosh/mediabay.c [POWERPC] Fix warning in pseries/eeh_driver.c [POWERPC] Add missing of_node_put in drivers/macintosh/therm_adt746x.c [POWERPC] Add missing of_node_put in drivers/macintosh/smu.c [POWERPC] Add missing of_node_put in pseries/nvram.c [POWERPC] Fix return value check logic in debugfs virq_mapping setup [POWERPC] Fix rmb to order cacheable vs. noncacheable powerpc/spufs: fix missed stop-and-signal event powerpc/spufs: synchronize interaction between spu exception handling and time slicing powerpc/spufs: remove class_0_dsisr from spu exception handling powerpc/spufs: wait for stable spu status in spu_stopped() [POWERPC] bootwrapper: add simpleImage* to list of boot targets [POWERPC] 83xx: MPC837xRDB's VSC7385 ethernet switch isn't on the MDIO bus [POWERPC] Updated Freescale PPC defconfigs [POWERPC] 8610: Update defconfig for MPC8610 HPCD [POWERPC] 85xx: MPC8548CDS - Fix size of PCIe IO space ...
| * | [POWERPC] Turn on ATA_SFF so we get SATA_SVW back in defconfigsPaul Mackerras2008-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This enables CONFIG_ATA_SFF in the defconfigs that are intended to work on a G5 powermac, i.e. g5_defconfig and ppc64_defconfig. Since the support for the SATA cell in the K2 chipset is provided by the sata_svw.c driver, and that depends on CONFIG_ATA_SFF, we need to turn that and CONFIG_SATA_SVW back on so we can get to the hard disk on G5s. Signed-off-by: Paul Mackerras <paulus@samba.org>
| * | [POWERPC] Remove ppc32's export of console_driversStephen Rothwell2008-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are no in-tree uses of the export any more and in linux-next there is a change that exports it globally which causes warnings: WARNING: vmlinux: 'console_drivers' exported twice. Previous export was in vmlinux and in one case (mpc85xx_defconfig) a build error: kernel/built-in.o: In function `__crc_console_drivers': (*ABS*+0x1eb0e6f5): multiple definition of `__crc_console_drivers' So remove the export now. Also, there is no longer any need to include linux/console.h. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
| * | [POWERPC] Fix -Os kernel builds with newer gcc versionsKumar Gala2008-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GCC 4.4.x looks to be adding support for generating out-of-line register saves/restores based on: http://gcc.gnu.org/ml/gcc-patches/2008-04/msg01678.html This breaks the kernel if we enable CONFIG_CC_OPTIMIZE_FOR_SIZE. To fix this we add the use the save/restore code from gcc and simplified it down for our needs (integer only). Additionally, we have to link this code into each module. The other solution was to add EXPORT_SYMBOL() which meant going through the trampoline which seemed nonsensical for these out-of-line routines. Finally, we add some checks to prom_init_check.sh to ignore the out-of-line save/restore functions. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
| * | [POWERPC] Fix bootwrapper builds with newer gcc versionsKumar Gala2008-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GCC 4.4.x looks to be adding support for generating out-of-line register saves/restores based on: http://gcc.gnu.org/ml/gcc-patches/2008-04/msg01678.html This breaks the bootwrapper as we'd need to link with libgcc to get the implementation of the register save/restores. To workaround this issue, we just stole the save/restore code from gcc and simplified it down for our needs (integer only). Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
| * | [POWERPC] Fix warning in pseries/eeh_driver.cAndrew Morton2008-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix this: /usr/src/devel/arch/powerpc/platforms/pseries/eeh_driver.c: In function 'print_device_node_tree': /usr/src/devel/arch/powerpc/platforms/pseries/eeh_driver.c:55: warning: ISO C90 forbids mixed declarations and code also make that function look like it's part of Linux. Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
| * | [POWERPC] Add missing of_node_put in pseries/nvram.cJulia Lawall2008-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | of_node_put is needed before discarding a value received from of_find_node_by_type, eg in error handling code. The semantic patch that makes the change is as follows: (http://www.emn.fr/x-info/coccinelle/) // <smpl> @@ struct device_node *n; struct device_node *n1; struct device_node *n2; statement S; identifier f1,f2; expression E1,E2; constant C; @@ n = of_find_node_by_type(...) ... if (!n) S ... when != of_node_put(n) when != n1 = f1(n,...) when != E1 = n when any when strict ( + of_node_put(n); return -C; | of_node_put(n); | n2 = f2(n,...) | E2 = n | return ...; ) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
| * | [POWERPC] Fix return value check logic in debugfs virq_mapping setupEmil Medve2008-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | debugfs_create_file() returns a non-NULL (non-zero) value in case of success, not a NULL value. This fixes this non-critical boot-time debugging error message: [ 1.316386] calling irq_debugfs_init+0x0/0x50 [ 1.316399] initcall irq_debugfs_init+0x0/0x50 returned -12 after 0 msecs [ 1.316411] initcall irq_debugfs_init+0x0/0x50 returned with error code -12 Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com> Acked-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
| * | Merge branch 'linux-2.6' into mergePaul Mackerras2008-06-16
| |\ \
| * \ \ Merge branch 'merge' of ↵Paul Mackerras2008-06-16
| |\ \ \ | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jk/spufs into merge