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2012-09-05xen: fix logical error in tlb flushingAlex Shi
While TLB_FLUSH_ALL gets passed as 'end' argument to flush_tlb_others(), the Xen code was made to check its 'start' parameter. That may give a incorrect op.cmd to MMUEXT_INVLPG_MULTI instead of MMUEXT_TLB_FLUSH_MULTI. Then it causes some page can not be flushed from TLB. This patch fixed this issue. Reported-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Alex Shi <alex.shi@intel.com> Acked-by: Jan Beulich <jbeulich@suse.com> Tested-by: Yongjie Ren <yongjie.ren@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-05Merge commit '4cb38750d49010ae72e718d46605ac9ba5a851b4' into ↵Konrad Rzeszutek Wilk
stable/for-linus-3.6 * commit '4cb38750d49010ae72e718d46605ac9ba5a851b4': (6849 commits) bcma: fix invalid PMU chip control masks [libata] pata_cmd64x: whitespace cleanup libata-acpi: fix up for acpi_pm_device_sleep_state API sata_dwc_460ex: device tree may specify dma_channel ahci, trivial: fixed coding style issues related to braces ahci_platform: add hibernation callbacks libata-eh.c: local functions should not be exposed globally libata-transport.c: local functions should not be exposed globally sata_dwc_460ex: support hardreset ata: use module_pci_driver drivers/ata/pata_pcmcia.c: adjust suspicious bit operation pata_imx: Convert to clk_prepare_enable/clk_disable_unprepare ahci: Enable SB600 64bit DMA on MSI K9AGM2 (MS-7327) v2 [libata] Prevent interface errors with Seagate FreeAgent GoFlex drivers/acpi/glue: revert accidental license-related 6b66d95895c bits libata-acpi: add missing inlines in libata.h i2c-omap: Add support for I2C_M_STOP message flag i2c: Fall back to emulated SMBus if the operation isn't supported natively i2c: Add SCCB support i2c-tiny-usb: Add support for the Robofuzz OSIF USB/I2C converter ...
2012-09-05xen/p2m: Fix one-off error in checking the P2M tree directory.Konrad Rzeszutek Wilk
We would traverse the full P2M top directory (from 0->MAX_DOMAIN_PAGES inclusive) when trying to figure out whether we can re-use some of the P2M middle leafs. Which meant that if the kernel was compiled with MAX_DOMAIN_PAGES=512 we would try to use the 512th entry. Fortunately for us the p2m_top_index has a check for this: BUG_ON(pfn >= MAX_P2M_PFN); which we hit and saw this: (XEN) domain_crash_sync called from entry.S (XEN) Domain 0 (vcpu#0) crashed on cpu#0: (XEN) ----[ Xen-4.1.2-OVM x86_64 debug=n Tainted: C ]---- (XEN) CPU: 0 (XEN) RIP: e033:[<ffffffff819cadeb>] (XEN) RFLAGS: 0000000000000212 EM: 1 CONTEXT: pv guest (XEN) rax: ffffffff81db5000 rbx: ffffffff81db4000 rcx: 0000000000000000 (XEN) rdx: 0000000000480211 rsi: 0000000000000000 rdi: ffffffff81db4000 (XEN) rbp: ffffffff81793db8 rsp: ffffffff81793d38 r8: 0000000008000000 (XEN) r9: 4000000000000000 r10: 0000000000000000 r11: ffffffff81db7000 (XEN) r12: 0000000000000ff8 r13: ffffffff81df1ff8 r14: ffffffff81db6000 (XEN) r15: 0000000000000ff8 cr0: 000000008005003b cr4: 00000000000026f0 (XEN) cr3: 0000000661795000 cr2: 0000000000000000 Fixes-Oracle-Bug: 14570662 CC: stable@vger.kernel.org # only for v3.5 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-23xen/setup: Fix one-off error when adding for-balloon PFNs to the P2M.Konrad Rzeszutek Wilk
When we are finished with return PFNs to the hypervisor, then populate it back, and also mark the E820 MMIO and E820 gaps as IDENTITY_FRAMEs, we then call P2M to set areas that can be used for ballooning. We were off by one, and ended up over-writting a P2M entry that most likely was an IDENTITY_FRAME. For example: 1-1 mapping on 40000->40200 1-1 mapping on bc558->bc5ac 1-1 mapping on bc5b4->bc8c5 1-1 mapping on bc8c6->bcb7c 1-1 mapping on bcd00->100000 Released 614 pages of unused memory Set 277889 page(s) to 1-1 mapping Populating 40200-40466 pfn range: 614 pages added => here we set from 40466 up to bc559 P2M tree to be INVALID_P2M_ENTRY. We should have done it up to bc558. The end result is that if anybody is trying to construct a PTE for PFN bc558 they end up with ~PAGE_PRESENT. CC: stable@vger.kernel.org Reported-by-and-Tested-by: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-17xen/p2m: Reuse existing P2M leafs if they are filled with 1:1 PFNs or INVALID.Konrad Rzeszutek Wilk
If P2M leaf is completly packed with INVALID_P2M_ENTRY or with 1:1 PFNs (so IDENTITY_FRAME type PFNs), we can swap the P2M leaf with either a p2m_missing or p2m_identity respectively. The old page (which was created via extend_brk or was grafted on from the mfn_list) can be re-used for setting new PFNs. This also means we can remove git commit: 5bc6f9888db5739abfa0cae279b4b442e4db8049 xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back which tried to fix this. and make the amount that is required to be reserved much smaller. CC: stable@vger.kernel.org # for 3.5 only. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-16Revert "xen PVonHVM: move shared_info to MMIO before kexec"Konrad Rzeszutek Wilk
This reverts commit 00e37bdb0113a98408de42db85be002f21dbffd3. During shutdown of PVHVM guests with more than 2VCPUs on certain machines we can hit the race where the replaced shared_info is not replaced fast enough and the PV time clock retries reading the same area over and over without any any success and is stuck in an infinite loop. Acked-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-02xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back.Konrad Rzeszutek Wilk
When we release pages back during bootup: Freeing 9d-100 pfn range: 99 pages freed Freeing 9cf36-9d0d2 pfn range: 412 pages freed Freeing 9f6bd-9f6bf pfn range: 2 pages freed Freeing 9f714-9f7bf pfn range: 171 pages freed Freeing 9f7e0-9f7ff pfn range: 31 pages freed Freeing 9f800-100000 pfn range: 395264 pages freed Released 395979 pages of unused memory We then try to populate those pages back. In the P2M tree however the space for those leafs must be reserved - as such we use extend_brk. We reserve 8MB of _brk space, which means we can fit over 1048576 PFNs - which is more than we should ever need. Without this, on certain compilation of the kernel we would hit: (XEN) domain_crash_sync called from entry.S (XEN) CPU: 0 (XEN) RIP: e033:[<ffffffff818aad3b>] (XEN) RFLAGS: 0000000000000206 EM: 1 CONTEXT: pv guest (XEN) rax: ffffffff81a7c000 rbx: 000000000000003d rcx: 0000000000001000 (XEN) rdx: ffffffff81a7b000 rsi: 0000000000001000 rdi: 0000000000001000 (XEN) rbp: ffffffff81801cd8 rsp: ffffffff81801c98 r8: 0000000000100000 (XEN) r9: ffffffff81a7a000 r10: 0000000000000001 r11: 0000000000000003 (XEN) r12: 0000000000000004 r13: 0000000000000004 r14: 000000000000003d (XEN) r15: 00000000000001e8 cr0: 000000008005003b cr4: 00000000000006f0 (XEN) cr3: 0000000125803000 cr2: 0000000000000000 (XEN) ds: 0000 es: 0000 fs: 0000 gs: 0000 ss: e02b cs: e033 (XEN) Guest stack trace from rsp=ffffffff81801c98: .. which is extend_brk hitting a BUG_ON. Interestingly enough, most of the time we are not going to hit this b/c the _brk space is quite large (v3.5): ffffffff81a25000 B __brk_base ffffffff81e43000 B __brk_limit = ~4MB. vs earlier kernels (with this back-ported), the space is smaller: ffffffff81a25000 B __brk_base ffffffff81a7b000 B __brk_limit = 344 kBytes. where we would certainly hit this and hit extend_brk. Note that git commit c3d93f880197953f86ab90d9da4744e926b38e33 (xen: populate correct number of pages when across mem boundary (v2)) exposed this bug). [v1: Made it 8MB of _brk space instead of 4MB per Jan's suggestion] CC: stable@vger.kernel.org #only for 3.5 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-26Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/mm changes from Peter Anvin: "The big change here is the patchset by Alex Shi to use INVLPG to flush only the affected pages when we only need to flush a small page range. It also removes the special INVALIDATE_TLB_VECTOR interrupts (32 vectors!) and replace it with an ordinary IPI function call." Fix up trivial conflicts in arch/x86/include/asm/apic.h (added code next to changed line) * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/tlb: Fix build warning and crash when building for !SMP x86/tlb: do flush_tlb_kernel_range by 'invlpg' x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR x86/tlb: enable tlb flush range support for x86 mm/mmu_gather: enable tlb flush range in generic mmu_gather x86/tlb: add tlb_flushall_shift knob into debugfs x86/tlb: add tlb_flushall_shift for specific CPU x86/tlb: fall back to flush all when meet a THP large page x86/flush_tlb: try flush_tlb_single one by one in flush_tlb_range x86/tlb_info: get last level TLB entry number of CPU x86: Add read_mostly declaration/definition to variables from smp.h x86: Define early read-mostly per-cpu macros
2012-07-24Merge tag 'stable/for-linus-3.6-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen update from Konrad Rzeszutek Wilk: "Features: * Performance improvement to lower the amount of traps the hypervisor has to do 32-bit guests. Mainly for setting PTE entries and updating TLS descriptors. * MCE polling driver to collect hypervisor MCE buffer and present them to /dev/mcelog. * Physical CPU online/offline support. When an privileged guest is booted it is present with virtual CPUs, which might have an 1:1 to physical CPUs but usually don't. This provides mechanism to offline/online physical CPUs. Bug-fixes for: * Coverity found fixes in the console and ACPI processor driver. * PVonHVM kexec fixes along with some cleanups. * Pages that fall within E820 gaps and non-RAM regions (and had been released to hypervisor) would be populated back, but potentially in non-RAM regions." * tag 'stable/for-linus-3.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: populate correct number of pages when across mem boundary (v2) xen PVonHVM: move shared_info to MMIO before kexec xen: simplify init_hvm_pv_info xen: remove cast from HYPERVISOR_shared_info assignment xen: enable platform-pci only in a Xen guest xen/pv-on-hvm kexec: shutdown watches from old kernel xen/x86: avoid updating TLS descriptors if they haven't changed xen/x86: add desc_equal() to compare GDT descriptors xen/mm: zero PTEs for non-present MFNs in the initial page table xen/mm: do direct hypercall in xen_set_pte() if batching is unavailable xen/hvc: Fix up checks when the info is allocated. xen/acpi: Fix potential memory leak. xen/mce: add .poll method for mcelog device driver xen/mce: schedule a workqueue to avoid sleep in atomic context xen/pcpu: Xen physical cpus online/offline sys interface xen/mce: Register native mce handler as vMCE bounce back point x86, MCE, AMD: Adjust initcall sequence for xen xen/mce: Add mcelog support for Xen platform
2012-07-22Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull smp/hotplug changes from Ingo Molnar: "Various cleanups to the SMP hotplug code - a continuing effort of Thomas et al" * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: smpboot: Remove leftover declaration smp: Remove num_booting_cpus() smp: Remove ipi_call_lock[_irq]()/ipi_call_unlock[_irq]() POWERPC: Smp: remove call to ipi_call_lock()/ipi_call_unlock() SPARC: SMP: Remove call to ipi_call_lock_irq()/ipi_call_unlock_irq() ia64: SMP: Remove call to ipi_call_lock_irq()/ipi_call_unlock_irq() x86-smp-remove-call-to-ipi_call_lock-ipi_call_unlock tile: SMP: Remove call to ipi_call_lock()/ipi_call_unlock() S390: Smp: remove call to ipi_call_lock()/ipi_call_unlock() parisc: Smp: remove call to ipi_call_lock()/ipi_call_unlock() mn10300: SMP: Remove call to ipi_call_lock()/ipi_call_unlock() hexagon: SMP: Remove call to ipi_call_lock()/ipi_call_unlock()
2012-07-19xen: populate correct number of pages when across mem boundary (v2)zhenzhong.duan
When populate pages across a mem boundary at bootup, the page count populated isn't correct. This is due to mem populated to non-mem region and ignored. Pfn range is also wrongly aligned when mem boundary isn't page aligned. For a dom0 booted with dom_mem=3368952K(0xcd9ff000-4k) dmesg diff is: [ 0.000000] Freeing 9e-100 pfn range: 98 pages freed [ 0.000000] 1-1 mapping on 9e->100 [ 0.000000] 1-1 mapping on cd9ff->100000 [ 0.000000] Released 98 pages of unused memory [ 0.000000] Set 206435 page(s) to 1-1 mapping -[ 0.000000] Populating cd9fe-cda00 pfn range: 1 pages added +[ 0.000000] Populating cd9fe-cd9ff pfn range: 1 pages added +[ 0.000000] Populating 100000-100061 pfn range: 97 pages added [ 0.000000] BIOS-provided physical RAM map: [ 0.000000] Xen: 0000000000000000 - 000000000009e000 (usable) [ 0.000000] Xen: 00000000000a0000 - 0000000000100000 (reserved) [ 0.000000] Xen: 0000000000100000 - 00000000cd9ff000 (usable) [ 0.000000] Xen: 00000000cd9ffc00 - 00000000cda53c00 (ACPI NVS) ... [ 0.000000] Xen: 0000000100000000 - 0000000100061000 (usable) [ 0.000000] Xen: 0000000100061000 - 000000012c000000 (unusable) ... [ 0.000000] MEMBLOCK configuration: ... -[ 0.000000] reserved[0x4] [0x000000cd9ff000-0x000000cd9ffbff], 0xc00 bytes -[ 0.000000] reserved[0x5] [0x00000100000000-0x00000100060fff], 0x61000 bytes Related xen memory layout: (XEN) Xen-e820 RAM map: (XEN) 0000000000000000 - 000000000009ec00 (usable) (XEN) 00000000000f0000 - 0000000000100000 (reserved) (XEN) 0000000000100000 - 00000000cd9ffc00 (usable) Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> [v2: If xen_do_chunk fail(populate), abort this chunk and any others] Suggested by David, thanks. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19xen PVonHVM: move shared_info to MMIO before kexecOlaf Hering
Currently kexec in a PVonHVM guest fails with a triple fault because the new kernel overwrites the shared info page. The exact failure depends on the size of the kernel image. This patch moves the pfn from RAM into MMIO space before the kexec boot. The pfn containing the shared_info is located somewhere in RAM. This will cause trouble if the current kernel is doing a kexec boot into a new kernel. The new kernel (and its startup code) can not know where the pfn is, so it can not reserve the page. The hypervisor will continue to update the pfn, and as a result memory corruption occours in the new kernel. One way to work around this issue is to allocate a page in the xen-platform pci device's BAR memory range. But pci init is done very late and the shared_info page is already in use very early to read the pvclock. So moving the pfn from RAM to MMIO is racy because some code paths on other vcpus could access the pfn during the small window when the old pfn is moved to the new pfn. There is even a small window were the old pfn is not backed by a mfn, and during that time all reads return -1. Because it is not known upfront where the MMIO region is located it can not be used right from the start in xen_hvm_init_shared_info. To minimise trouble the move of the pfn is done shortly before kexec. This does not eliminate the race because all vcpus are still online when the syscore_ops will be called. But hopefully there is no work pending at this point in time. Also the syscore_op is run last which reduces the risk further. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19xen: simplify init_hvm_pv_infoOlaf Hering
init_hvm_pv_info is called only in PVonHVM context, move it into ifdef. init_hvm_pv_info does not fail, make it a void function. remove arguments from init_hvm_pv_info because they are not used by the caller. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19xen: remove cast from HYPERVISOR_shared_info assignmentOlaf Hering
Both have type struct shared_info so no cast is needed. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19xen/x86: avoid updating TLS descriptors if they haven't changedDavid Vrabel
When switching tasks in a Xen PV guest, avoid updating the TLS descriptors if they haven't changed. This improves the speed of context switches by almost 10% as much of the time the descriptors are the same or only one is different. The descriptors written into the GDT by Xen are modified from the values passed in the update_descriptor hypercall so we keep shadow copies of the three TLS descriptors to compare against. lmbench3 test Before After Improvement -------------------------------------------- lat_ctx -s 32 24 7.19 6.52 9% lat_pipe 12.56 11.66 7% Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19xen/x86: add desc_equal() to compare GDT descriptorsDavid Vrabel
Signed-off-by: David Vrabel <david.vrabel@citrix.com> [v1: Moving it to the Xen file] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19xen/mm: zero PTEs for non-present MFNs in the initial page tableDavid Vrabel
When constructing the initial page tables, if the MFN for a usable PFN is missing in the p2m then that frame is initially ballooned out. In this case, zero the PTE (as in decrease_reservation() in drivers/xen/balloon.c). This is obviously safe instead of having an valid PTE with an MFN of INVALID_P2M_ENTRY (~0). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19xen/mm: do direct hypercall in xen_set_pte() if batching is unavailableDavid Vrabel
In xen_set_pte() if batching is unavailable (because the caller is in an interrupt context such as handling a page fault) it would fall back to using native_set_pte() and trapping and emulating the PTE write. On 32-bit guests this requires two traps for each PTE write (one for each dword of the PTE). Instead, do one mmu_update hypercall directly. During construction of the initial page tables, continue to use native_set_pte() because most of the PTEs being set are in writable and unpinned pages (see phys_pmd_init() in arch/x86/mm/init_64.c) and using a hypercall for this is very expensive. This significantly improves page fault performance in 32-bit PV guests. lmbench3 test Before After Improvement ---------------------------------------------- lat_pagefault 3.18 us 2.32 us 27% lat_proc fork 356 us 313.3 us 11% Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19xen/mce: Register native mce handler as vMCE bounce back pointLiu, Jinsong
When Xen hypervisor inject vMCE to guest, use native mce handler to handle it Signed-off-by: Ke, Liping <liping.ke@intel.com> Signed-off-by: Jiang, Yunhong <yunhong.jiang@intel.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-19xen/mce: Add mcelog support for Xen platformLiu, Jinsong
When MCA error occurs, it would be handled by Xen hypervisor first, and then the error information would be sent to initial domain for logging. This patch gets error information from Xen hypervisor and convert Xen format error into Linux format mcelog. This logic is basically self-contained, not touching other kernel components. By using tools like mcelog tool users could read specific error information, like what they did under native Linux. To test follow directions outlined in Documentation/acpi/apei/einj.txt Acked-and-tested-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Ke, Liping <liping.ke@intel.com> Signed-off-by: Jiang, Yunhong <yunhong.jiang@intel.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-05Merge branch 'x86/cpu' into perf/coreIngo Molnar
Merge this branch because we changed the wrmsr*_safe() API and there's a conflict. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-06-27x86/flush_tlb: try flush_tlb_single one by one in flush_tlb_rangeAlex Shi
x86 has no flush_tlb_range support in instruction level. Currently the flush_tlb_range just implemented by flushing all page table. That is not the best solution for all scenarios. In fact, if we just use 'invlpg' to flush few lines from TLB, we can get the performance gain from later remain TLB lines accessing. But the 'invlpg' instruction costs much of time. Its execution time can compete with cr3 rewriting, and even a bit more on SNB CPU. So, on a 512 4KB TLB entries CPU, the balance points is at: (512 - X) * 100ns(assumed TLB refill cost) = X(TLB flush entries) * 100ns(assumed invlpg cost) Here, X is 256, that is 1/2 of 512 entries. But with the mysterious CPU pre-fetcher and page miss handler Unit, the assumed TLB refill cost is far lower then 100ns in sequential access. And 2 HT siblings in one core makes the memory access more faster if they are accessing the same memory. So, in the patch, I just do the change when the target entries is less than 1/16 of whole active tlb entries. Actually, I have no data support for the percentage '1/16', so any suggestions are welcomed. As to hugetlb, guess due to smaller page table, and smaller active TLB entries, I didn't see benefit via my benchmark, so no optimizing now. My micro benchmark show in ideal scenarios, the performance improves 70 percent in reading. And in worst scenario, the reading/writing performance is similar with unpatched 3.4-rc4 kernel. Here is the reading data on my 2P * 4cores *HT NHM EP machine, with THP 'always': multi thread testing, '-t' paramter is thread number: with patch unpatched 3.4-rc4 ./mprotect -t 1 14ns 24ns ./mprotect -t 2 13ns 22ns ./mprotect -t 4 12ns 19ns ./mprotect -t 8 14ns 16ns ./mprotect -t 16 28ns 26ns ./mprotect -t 32 54ns 51ns ./mprotect -t 128 200ns 199ns Single process with sequencial flushing and memory accessing: with patch unpatched 3.4-rc4 ./mprotect 7ns 11ns ./mprotect -p 4096 -l 8 -n 10240 21ns 21ns [ hpa: http://lkml.kernel.org/r/1B4B44D9196EFF41AE41FDA404FC0A100BFF94@SHSMSX101.ccr.corp.intel.com has additional performance numbers. ] Signed-off-by: Alex Shi <alex.shi@intel.com> Link: http://lkml.kernel.org/r/1340845344-27557-3-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-06-15Merge tag 'stable/for-linus-3.5-rc2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull five Xen bug-fixes from Konrad Rzeszutek Wilk: - When booting as PVHVM we would try to use PV console - but would not validate the parameters causing us to crash during restore b/c we re-use the wrong event channel. - When booting on machines with SR-IOV PCI bridge we didn't check for the bridge and tried to use it. - Under AMD machines would advertise the APERFMPERF resulting in needless amount of MSRs from the guest. - A global value (xen_released_pages) was not subtracted at bootup when pages were added back in. This resulted in the balloon worker having the wrong account of how many pages were truly released. - Fix dead-lock when xen-blkfront is run in the same domain as xen-blkback. * tag 'stable/for-linus-3.5-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: mark local pages as FOREIGN in the m2p_override xen/setup: filter APERFMPERF cpuid feature out xen/balloon: Subtract from xen_released_pages the count that is populated. xen/pci: Check for PCI bridge before using it. xen/events: Add WARN_ON when quick lookup found invalid type. xen/hvc: Check HVM_PARAM_CONSOLE_[EVTCHN|PFN] for correctness. xen/hvc: Fix error cases around HVM_PARAM_CONSOLE_PFN xen/hvc: Collapse error logic.
2012-06-14xen: mark local pages as FOREIGN in the m2p_overrideStefano Stabellini
When the frontend and the backend reside on the same domain, even if we add pages to the m2p_override, these pages will never be returned by mfn_to_pfn because the check "get_phys_to_machine(pfn) != mfn" will always fail, so the pfn of the frontend will be returned instead (resulting in a deadlock because the frontend pages are already locked). INFO: task qemu-system-i38:1085 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. qemu-system-i38 D ffff8800cfc137c0 0 1085 1 0x00000000 ffff8800c47ed898 0000000000000282 ffff8800be4596b0 00000000000137c0 ffff8800c47edfd8 ffff8800c47ec010 00000000000137c0 00000000000137c0 ffff8800c47edfd8 00000000000137c0 ffffffff82213020 ffff8800be4596b0 Call Trace: [<ffffffff81101ee0>] ? __lock_page+0x70/0x70 [<ffffffff81a0fdd9>] schedule+0x29/0x70 [<ffffffff81a0fe80>] io_schedule+0x60/0x80 [<ffffffff81101eee>] sleep_on_page+0xe/0x20 [<ffffffff81a0e1ca>] __wait_on_bit_lock+0x5a/0xc0 [<ffffffff81101ed7>] __lock_page+0x67/0x70 [<ffffffff8106f750>] ? autoremove_wake_function+0x40/0x40 [<ffffffff811867e6>] ? bio_add_page+0x36/0x40 [<ffffffff8110b692>] set_page_dirty_lock+0x52/0x60 [<ffffffff81186021>] bio_set_pages_dirty+0x51/0x70 [<ffffffff8118c6b4>] do_blockdev_direct_IO+0xb24/0xeb0 [<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00 [<ffffffff8118ca95>] __blockdev_direct_IO+0x55/0x60 [<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00 [<ffffffff811e91c8>] ext3_direct_IO+0xf8/0x390 [<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00 [<ffffffff81004b60>] ? xen_mc_flush+0xb0/0x1b0 [<ffffffff81104027>] generic_file_aio_read+0x737/0x780 [<ffffffff813bedeb>] ? gnttab_map_refs+0x15b/0x1e0 [<ffffffff811038f0>] ? find_get_pages+0x150/0x150 [<ffffffff8119736c>] aio_rw_vect_retry+0x7c/0x1d0 [<ffffffff811972f0>] ? lookup_ioctx+0x90/0x90 [<ffffffff81198856>] aio_run_iocb+0x66/0x1a0 [<ffffffff811998b8>] do_io_submit+0x708/0xb90 [<ffffffff81199d50>] sys_io_submit+0x10/0x20 [<ffffffff81a18d69>] system_call_fastpath+0x16/0x1b The explanation is in the comment within the code: We need to do this because the pages shared by the frontend (xen-blkfront) can be already locked (lock_page, called by do_read_cache_page); when the userspace backend tries to use them with direct_IO, mfn_to_pfn returns the pfn of the frontend, so do_blockdev_direct_IO is going to try to lock the same pages again resulting in a deadlock. A simplified call graph looks like this: pygrub QEMU ----------------------------------------------- do_read_cache_page io_submit | | lock_page ext3_direct_IO | bio_add_page | lock_page Internally the xen-blkback uses m2p_add_override to swizzle (temporarily) a 'struct page' to have a different MFN (so that it can point to another guest). It also can easily find out whether another pfn corresponding to the mfn exists in the m2p, and can set the FOREIGN bit in the p2m, making sure that mfn_to_pfn returns the pfn of the backend. This allows the backend to perform direct_IO on these pages, but as a side effect prevents the frontend from using get_user_pages_fast on them while they are being shared with the backend. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-06-07x86, pvops: Remove hooks for {rd,wr}msr_safe_regsAndre Przywara
There were paravirt_ops hooks for the full register set variant of {rd,wr}msr_safe which are actually not used by anyone anymore. Remove them to make the code cleaner and avoid silent breakages when the pvops members were uninitialized. This has been boot-tested natively and under Xen with PVOPS enabled and disabled on one machine. Signed-off-by: Andre Przywara <andre.przywara@amd.com> Link: http://lkml.kernel.org/r/1338562358-28182-2-git-send-email-bp@amd64.org Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-06-05x86-smp-remove-call-to-ipi_call_lock-ipi_call_unlockYong Zhang
ipi_call_lock/unlock() lock resp. unlock call_function.lock. This lock protects only the call_function data structure itself, but it's completely unrelated to cpu_online_mask. The mask to which the IPIs are sent is calculated before call_function.lock is taken in smp_call_function_many(), so the locking around set_cpu_online() is pointless and can be removed. [ tglx: Massaged changelog ] Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> Cc: ralf@linux-mips.org Cc: sshtylyov@mvista.com Cc: david.daney@cavium.com Cc: nikunj@linux.vnet.ibm.com Cc: paulmck@linux.vnet.ibm.com Cc: axboe@kernel.dk Cc: peterz@infradead.org Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Link: http://lkml.kernel.org/r/1338275765-3217-7-git-send-email-yong.zhang0@gmail.com Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-31xen/setup: filter APERFMPERF cpuid feature outAndre Przywara
Xen PV kernels allow access to the APERF/MPERF registers to read the effective frequency. Access to the MSRs is however redirected to the currently scheduled physical CPU, making consecutive read and compares unreliable. In addition each rdmsr traps into the hypervisor. So to avoid bogus readouts and expensive traps, disable the kernel internal feature flag for APERF/MPERF if running under Xen. This will a) remove the aperfmperf flag from /proc/cpuinfo b) not mislead the power scheduler (arch/x86/kernel/cpu/sched.c) to use the feature to improve scheduling (by default disabled) c) not mislead the cpufreq driver to use the MSRs This does not cover userland programs which access the MSRs via the device file interface, but this will be addressed separately. Signed-off-by: Andre Przywara <andre.przywara@amd.com> Cc: stable@vger.kernel.org # v3.0+ Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-30x86, amd, xen: Avoid NULL pointer paravirt referencesKonrad Rzeszutek Wilk
Stub out MSR methods that aren't actually needed. This fixes a crash as Xen Dom0 on AMD Trinity systems. A bigger patch should be added to remove the paravirt machinery completely for the methods which apparently have no users! Reported-by: Andre Przywara <andre.przywara@amd.com> Link: http://lkml.kernel.org/r/20120530222356.GA28417@andromeda.dapyr.net Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: <stable@vger.kernel.org>
2012-05-30xen/balloon: Subtract from xen_released_pages the count that is populated.Konrad Rzeszutek Wilk
We did not take into account that xen_released_pages would be used outside the initial E820 parsing code. As such we would did not subtract from xen_released_pages the count of pages that we had populated back (instead we just did a simple extra_pages = released - populated). The balloon driver uses xen_released_pages to set the initial current_pages count. If this is wrong (too low) then when a new (higher) target is set, the balloon driver will request too many pages from Xen." This fixes errors such as: (XEN) memory.c:133:d0 Could not allocate order=0 extent: id=0 memflags=0 (51 of 512) during bootup and free_memory : 0 where the free_memory should be 128. Acked-by: David Vrabel <david.vrabel@citrix.com> [v1: Per David's review made the git commit better] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-24Merge tag 'stable/for-linus-3.5-rc0-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen updates from Konrad Rzeszutek Wilk: "Features: * Extend the APIC ops implementation and add IRQ_WORKER vector support so that 'perf' can work properly. * Fix self-ballooning code, and balloon logic when booting as initial domain. * Move array printing code to generic debugfs * Support XenBus domains. * Lazily free grants when a domain is dead/non-existent. * In M2P code use batching calls Bug-fixes: * Fix NULL dereference in allocation failure path (hvc_xen) * Fix unbinding of IRQ_WORKER vector during vCPU hot-unplug * Fix HVM guest resume - we would leak an PIRQ value instead of reusing the existing one." Fix up add-add onflicts in arch/x86/xen/enlighten.c due to addition of apic ipi interface next to the new apic_id functions. * tag 'stable/for-linus-3.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: do not map the same GSI twice in PVHVM guests. hvc_xen: NULL dereference on allocation failure xen: Add selfballoning memory reservation tunable. xenbus: Add support for xenbus backend in stub domain xen/smp: unbind irqworkX when unplugging vCPUs. xen: enter/exit lazy_mmu_mode around m2p_override calls xen/acpi/sleep: Enable ACPI sleep via the __acpi_os_prepare_sleep xen: implement IRQ_WORK_VECTOR handler xen: implement apic ipi interface xen/setup: update VA mapping when releasing memory during setup xen/setup: Combine the two hypercall functions - since they are quite similar. xen/setup: Populate freed MFNs from non-RAM E820 entries and gaps to E820 RAM xen/setup: Only print "Freeing XXX-YYY pfn range: Z pages freed" if Z > 0 xen/gnttab: add deferred freeing logic debugfs: Add support to print u32 array in debugfs xen/p2m: An early bootup variant of set_phys_to_machine xen/p2m: Collapse early_alloc_p2m_middle redundant checks. xen/p2m: Allow alloc_p2m_middle to call reserve_brk depending on argument xen/p2m: Move code around to allow for better re-usage.
2012-05-23Merge branch 'x86-extable-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull exception table generation updates from Ingo Molnar: "The biggest change here is to allow the build-time sorting of the exception table, to speed up booting. This is achieved by the architecture enabling BUILDTIME_EXTABLE_SORT. This option is enabled for x86 and MIPS currently. On x86 a number of fixes and changes were needed to allow build-time sorting of the exception table, in particular a relocation invariant exception table format was needed. This required the abstracting out of exception table protocol and the removal of 20 years of accumulated assumptions about the x86 exception table format. While at it, this tree also cleans up various other aspects of exception handling, such as early(er) exception handling for rdmsr_safe() et al. All in one, as the result of these changes the x86 exception code is now pretty nice and modern. As an added bonus any regressions in this code will be early and violent crashes, so if you see any of those, you'll know whom to blame!" Fix up trivial conflicts in arch/{mips,x86}/Kconfig files due to nearby modifications of other core architecture options. * 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits) Revert "x86, extable: Disable presorted exception table for now" scripts/sortextable: Handle relative entries, and other cleanups x86, extable: Switch to relative exception table entries x86, extable: Disable presorted exception table for now x86, extable: Add _ASM_EXTABLE_EX() macro x86, extable: Remove open-coded exception table entries in arch/x86/ia32/ia32entry.S x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/xsave.h x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/kvm_host.h x86, extable: Remove the now-unused __ASM_EX_SEC macros x86, extable: Remove open-coded exception table entries in arch/x86/xen/xen-asm_32.S x86, extable: Remove open-coded exception table entries in arch/x86/um/checksum_32.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/usercopy_32.c x86, extable: Remove open-coded exception table entries in arch/x86/lib/putuser.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/getuser.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/csum-copy_64.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_nocache_64.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S x86, extable: Remove open-coded exception table entries in arch/x86/lib/checksum_32.S x86, extable: Remove open-coded exception table entries in arch/x86/kernel/test_rodata.c x86, extable: Remove open-coded exception table entries in arch/x86/kernel/entry_64.S ...
2012-05-22Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/apic changes from Ingo Molnar: "Most of the changes are about helping virtualized guest kernels achieve better performance." Fix up trivial conflicts with the iommu updates to arch/x86/kernel/apic/io_apic.c * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Implement EIO micro-optimization x86/apic: Add apic->eoi_write() callback x86/apic: Use symbolic APIC_EOI_ACK x86/apic: Fix typo EIO_ACK -> EOI_ACK and document it x86/xen/apic: Add missing #include <xen/xen.h> x86/apic: Only compile local function if used with !CONFIG_GENERIC_PENDING_IRQ x86/apic: Fix UP boot crash x86: Conditionally update time when ack-ing pending irqs xen/apic: implement io apic read with hypercall Revert "xen/x86: Workaround 'x86/ioapic: Add register level checks to detect bogus io-apic entries'" xen/x86: Implement x86_apic_ops x86/apic: Replace io_apic_ops with x86_io_apic_ops.
2012-05-21Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull smp hotplug cleanups from Thomas Gleixner: "This series is merily a cleanup of code copied around in arch/* and not changing any of the real cpu hotplug horrors yet. I wish I'd had something more substantial for 3.5, but I underestimated the lurking horror..." Fix up trivial conflicts in arch/{arm,sparc,x86}/Kconfig and arch/sparc/include/asm/thread_info_32.h * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (79 commits) um: Remove leftover declaration of alloc_task_struct_node() task_allocator: Use config switches instead of magic defines sparc: Use common threadinfo allocator score: Use common threadinfo allocator sh-use-common-threadinfo-allocator mn10300: Use common threadinfo allocator powerpc: Use common threadinfo allocator mips: Use common threadinfo allocator hexagon: Use common threadinfo allocator m32r: Use common threadinfo allocator frv: Use common threadinfo allocator cris: Use common threadinfo allocator x86: Use common threadinfo allocator c6x: Use common threadinfo allocator fork: Provide kmemcache based thread_info allocator tile: Use common threadinfo allocator fork: Provide weak arch_release_[task_struct|thread_info] functions fork: Move thread info gfp flags to header fork: Remove the weak insanity sh: Remove cpu_idle_wait() ...
2012-05-21xen/smp: unbind irqworkX when unplugging vCPUs.Konrad Rzeszutek Wilk
The git commit 1ff2b0c303698e486f1e0886b4d9876200ef8ca5 "xen: implement IRQ_WORK_VECTOR handler" added the functionality to have a per-cpu "irqworkX" for the IPI APIC functionality. However it missed the unbind when a vCPU is unplugged resulting in an orphaned per-cpu interrupt line for unplugged vCPU: 30: 216 0 xen-dyn-event hvc_console 31: 810 4 xen-dyn-event eth0 32: 29 0 xen-dyn-event blkif - 36: 0 0 xen-percpu-ipi irqwork2 - 37: 287 0 xen-dyn-event xenbus + 36: 287 0 xen-dyn-event xenbus NMI: 0 0 Non-maskable interrupts LOC: 0 0 Local timer interrupts SPU: 0 0 Spurious interrupts Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-18x86/xen/apic: Add missing #include <xen/xen.h>Ingo Molnar
This file depends on <xen/xen.h>, but the dependency was hidden due to: <asm/acpi.h> -> <asm/trampoline.h> -> <asm/io.h> -> <xen/xen.h> With the removal of <asm/trampoline.h>, this exposed the missing Cc: Len Brown <lenb@kernel.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/n/tip-7ccybvue6mw6wje3uxzzcglj@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-08Merge branch 'smp/threadalloc' into smp/hotplugThomas Gleixner
Reason: Pull in the separate branch which was created so arch/tile can base further work on it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-07Merge branch 'stable/autoballoon.v5.2' into stable/for-linus-3.5Konrad Rzeszutek Wilk
* stable/autoballoon.v5.2: xen/setup: update VA mapping when releasing memory during setup xen/setup: Combine the two hypercall functions - since they are quite similar. xen/setup: Populate freed MFNs from non-RAM E820 entries and gaps to E820 RAM xen/setup: Only print "Freeing XXX-YYY pfn range: Z pages freed" if Z > 0 xen/p2m: An early bootup variant of set_phys_to_machine xen/p2m: Collapse early_alloc_p2m_middle redundant checks. xen/p2m: Allow alloc_p2m_middle to call reserve_brk depending on argument xen/p2m: Move code around to allow for better re-usage.
2012-05-07xen/acpi/sleep: Enable ACPI sleep via the __acpi_os_prepare_sleepKonrad Rzeszutek Wilk
Provide the registration callback to call in the Xen's ACPI sleep functionality. This means that during S3/S5 we make a hypercall XENPF_enter_acpi_sleep with the proper PM1A/PM1B registers. Based of Ke Yu's <ke.yu@intel.com> initial idea. [ From http://xenbits.xensource.com/linux-2.6.18-xen.hg change c68699484a65 ] [v1: Added Copyright and license] [v2: Added check if PM1A/B the 16-bits MSB contain something. The spec only uses 16-bits but might have more in future] Signed-off-by: Liang Tang <liang.tang@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07xen: implement IRQ_WORK_VECTOR handlerLin Ming
Signed-off-by: Lin Ming <mlin@ss.pku.edu.cn> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07xen: implement apic ipi interfaceBen Guthro
Map native ipi vector to xen vector. Implement apic ipi interface with xen_send_IPI_one. Tested-by: Steven Noonan <steven@uplinklabs.net> Signed-off-by: Ben Guthro <ben@guthro.net> Signed-off-by: Lin Ming <mlin@ss.pku.edu.cn> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07xen/setup: update VA mapping when releasing memory during setupDavid Vrabel
In xen_memory_setup(), if a page that is being released has a VA mapping this must also be updated. Otherwise, the page will be not released completely -- it will still be referenced in Xen and won't be freed util the mapping is removed and this prevents it from being reallocated at a different PFN. This was already being done for the ISA memory region in xen_ident_map_ISA() but on many systems this was omitting a few pages as many systems marked a few pages below the ISA memory region as reserved in the e820 map. This fixes errors such as: (XEN) page_alloc.c:1148:d0 Over-allocation for domain 0: 2097153 > 2097152 (XEN) memory.c:133:d0 Could not allocate order=0 extent: id=0 memflags=0 (0 of 17) Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07xen/setup: Combine the two hypercall functions - since they are quite similar.Konrad Rzeszutek Wilk
They use the same set of arguments, so it is just the matter of using the proper hypercall. Acked-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07xen/setup: Populate freed MFNs from non-RAM E820 entries and gaps to E820 RAMKonrad Rzeszutek Wilk
When the Xen hypervisor boots a PV kernel it hands it two pieces of information: nr_pages and a made up E820 entry. The nr_pages value defines the range from zero to nr_pages of PFNs which have a valid Machine Frame Number (MFN) underneath it. The E820 mirrors that (with the VGA hole): BIOS-provided physical RAM map: Xen: 0000000000000000 - 00000000000a0000 (usable) Xen: 00000000000a0000 - 0000000000100000 (reserved) Xen: 0000000000100000 - 0000000080800000 (usable) The fun comes when a PV guest that is run with a machine E820 - that can either be the initial domain or a PCI PV guest, where the E820 looks like the normal thing: BIOS-provided physical RAM map: Xen: 0000000000000000 - 000000000009e000 (usable) Xen: 000000000009ec00 - 0000000000100000 (reserved) Xen: 0000000000100000 - 0000000020000000 (usable) Xen: 0000000020000000 - 0000000020200000 (reserved) Xen: 0000000020200000 - 0000000040000000 (usable) Xen: 0000000040000000 - 0000000040200000 (reserved) Xen: 0000000040200000 - 00000000bad80000 (usable) Xen: 00000000bad80000 - 00000000badc9000 (ACPI NVS) .. With that overlaying the nr_pages directly on the E820 does not work as there are gaps and non-RAM regions that won't be used by the memory allocator. The 'xen_release_chunk' helps with that by punching holes in the P2M (PFN to MFN lookup tree) for those regions and tells us that: Freeing 20000-20200 pfn range: 512 pages freed Freeing 40000-40200 pfn range: 512 pages freed Freeing bad80-badf4 pfn range: 116 pages freed Freeing badf6-bae7f pfn range: 137 pages freed Freeing bb000-100000 pfn range: 282624 pages freed Released 283999 pages of unused memory Those 283999 pages are subtracted from the nr_pages and are returned to the hypervisor. The end result is that the initial domain boots with 1GB less memory as the nr_pages has been subtracted by the amount of pages residing within the PCI hole. It can balloon up to that if desired using 'xl mem-set 0 8092', but the balloon driver is not always compiled in for the initial domain. This patch, implements the populate hypercall (XENMEM_populate_physmap) which increases the the domain with the same amount of pages that were released. The other solution (that did not work) was to transplant the MFN in the P2M tree - the ones that were going to be freed were put in the E820_RAM regions past the nr_pages. But the modifications to the M2P array (the other side of creating PTEs) were not carried away. As the hypervisor is the only one capable of modifying that and the only two hypercalls that would do this are: the update_va_mapping (which won't work, as during initial bootup only PFNs up to nr_pages are mapped in the guest) or via the populate hypercall. The end result is that the kernel can now boot with the nr_pages without having to subtract the 283999 pages. On a 8GB machine, with various dom0_mem= parameters this is what we get: no dom0_mem -Memory: 6485264k/9435136k available (5817k kernel code, 1136060k absent, 1813812k reserved, 2899k data, 696k init) +Memory: 7619036k/9435136k available (5817k kernel code, 1136060k absent, 680040k reserved, 2899k data, 696k init) dom0_mem=3G -Memory: 2616536k/9435136k available (5817k kernel code, 1136060k absent, 5682540k reserved, 2899k data, 696k init) +Memory: 2703776k/9435136k available (5817k kernel code, 1136060k absent, 5595300k reserved, 2899k data, 696k init) dom0_mem=max:3G -Memory: 2696732k/4281724k available (5817k kernel code, 1136060k absent, 448932k reserved, 2899k data, 696k init) +Memory: 2702204k/4281724k available (5817k kernel code, 1136060k absent, 443460k reserved, 2899k data, 696k init) And the 'xm list' or 'xl list' now reflect what the dom0_mem= argument is. Acked-by: David Vrabel <david.vrabel@citrix.com> [v2: Use populate hypercall] [v3: Remove debug printks] [v4: Simplify code] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07xen/setup: Only print "Freeing XXX-YYY pfn range: Z pages freed" if Z > 0Konrad Rzeszutek Wilk
Otherwise we can get these meaningless: Freeing bad80-badf4 pfn range: 0 pages freed We also can do this for the summary ones - no point of printing "Set 0 page(s) to 1-1 mapping" Acked-by: David Vrabel <david.vrabel@citrix.com> [v1: Extended to the summary printks] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07xen/pci: don't use PCI BIOS service for configuration space accessesDavid Vrabel
The accessing PCI configuration space with the PCI BIOS32 service does not work in PV guests. On systems without MMCONFIG or where the BIOS hasn't marked the MMCONFIG region as reserved in the e820 map, the BIOS service is probed (even though direct access is preferred) and this hangs. CC: stable@kernel.org Acked-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> [v1: Fixed compile error when CONFIG_PCI is not set] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07xen/pte: Fix crashes when trying to see non-existent PGD/PMD/PUD/PTEsKonrad Rzeszutek Wilk
If I try to do "cat /sys/kernel/debug/kernel_page_tables" I end up with: BUG: unable to handle kernel paging request at ffffc7fffffff000 IP: [<ffffffff8106aa51>] ptdump_show+0x221/0x480 PGD 0 Oops: 0000 [#1] SMP CPU 0 .. snip.. RAX: 0000000000000000 RBX: ffffc00000000fff RCX: 0000000000000000 RDX: 0000800000000000 RSI: 0000000000000000 RDI: ffffc7fffffff000 which is due to the fact we are trying to access a PFN that is not accessible to us. The reason (at least in this case) was that PGD[256] is set to __HYPERVISOR_VIRT_START which was setup (by the hypervisor) to point to a read-only linear map of the MFN->PFN array. During our parsing we would get the MFN (a valid one), try to look it up in the MFN->PFN tree and find it invalid and return ~0 as PFN. Then pte_mfn_to_pfn would happilly feed that in, attach the flags and return it back to the caller. 'ptdump_show' bitshifts it and gets and invalid value that it tries to dereference. Instead of doing all of that, we detect the ~0 case and just return !_PAGE_PRESENT. This bug has been in existence .. at least until 2.6.37 (yikes!) CC: stable@kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-07xen/apic: Return the APIC ID (and version) for CPU 0.Konrad Rzeszutek Wilk
On x86_64 on AMD machines where the first APIC_ID is not zero, we get: ACPI: LAPIC (acpi_id[0x01] lapic_id[0x10] enabled) BIOS bug: APIC version is 0 for CPU 1/0x10, fixing up to 0x10 BIOS bug: APIC version mismatch, boot CPU: 0, CPU 1: version 10 which means that when the ACPI processor driver loads and tries to parse the _Pxx states it fails to do as, as it ends up calling acpi_get_cpuid which does this: for_each_possible_cpu(i) { if (cpu_physical_id(i) == apic_id) return i; } And the bootup CPU, has not been found so it fails and returns -1 for the first CPU - which then subsequently in the loop that "acpi_processor_get_info" does results in returning an error, which means that "acpi_processor_add" failing and per_cpu(processor) is never set (and is NULL). That means that when xen-acpi-processor tries to load (much much later on) and parse the P-states it gets -ENODEV from acpi_processor_register_performance() (which tries to read the per_cpu(processor)) and fails to parse the data. Reported-by-and-Tested-by: Stefan Bader <stefan.bader@canonical.com> Suggested-by: Boris Ostrovsky <boris.ostrovsky@amd.com> [v2: Bit-shift APIC ID by 24 bits] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-01xen/apic: implement io apic read with hypercallLin Ming
Implements xen_io_apic_read with hypercall, so it returns proper IO-APIC information instead of fabricated one. Fallback to return an emulated IO_APIC values if hypercall fails. [v2: fallback to return an emulated IO_APIC values if hypercall fails] Signed-off-by: Lin Ming <mlin@ss.pku.edu.cn> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-01Revert "xen/x86: Workaround 'x86/ioapic: Add register level checks to detect ↵Konrad Rzeszutek Wilk
bogus io-apic entries'" This reverts commit 2531d64b6fe2724dc432b67d8dc66bd45621da0b. The two patches: x86/apic: Replace io_apic_ops with x86_io_apic_ops. xen/x86: Implement x86_apic_ops take care of fixing it properly. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-05-01xen/x86: Implement x86_apic_opsKonrad Rzeszutek Wilk
Or rather just implement one different function as opposed to the native one : the read function. We synthesize the values. Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> [v1: Rebased on top of tip/x86/urgent] [v2: Return 0xfd instead of 0xff in the default case] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>