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path: root/drivers/gpu/drm/i915/gvt/gtt.h
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2019-03-04drm/i915/gvt: Add mutual lock for ppgtt mm LRU listZhenyu Wang
This adds mutex to guard against update of global ppgtt mm LRU list. To resolve error found as below warning. [73130.012162] ------------[ cut here ]------------ [73130.012168] list_add corruption. prev->next should be next (ffff995f970cca50), but was 0000000000000000. (prev=ffff995f0dc5bdf8). [73130.012181] WARNING: CPU: 3 PID: 82 at lib/list_debug.c:28 __list_add_valid+0x4d/0x70 [73130.012183] Modules linked in: btrfs(E) xor(E) zstd_decompress(E) zstd_compress(E) raid6_pq(E) dm_mod(E) kvmgt(E) fuse(E) xt_addrtype(E) nft_compat(E) xt_conntrack(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) libcrc32c(E) br_netfilter(E) bridge(E) stp(E) llc(E) overlay(E) devlink(E) nf_tables(E) nfnetlink(E) loop(E) x86_pkg_temp_thermal(E) intel_powerclamp(E) coretemp(E) crct10dif_pclmul(E) crc32_pclmul(E) ghash_clmulni_intel(E) mei_me(E) aesni_intel(E) aes_x86_64(E) crypto_simd(E) cryptd(E) glue_helper(E) intel_cstate(E) intel_uncore(E) mei(E) intel_pch_thermal(E) intel_rapl_perf(E) pcspkr(E) iTCO_wdt(E) iTCO_vendor_support(E) idma64(E) sg(E) virt_dma(E) acpi_pad(E) evdev(E) binfmt_misc(E) ip_tables(E) x_tables(E) ipv6(E) autofs4(E) hid_generic(E) usbhid(E) hid(E) ext4(E) crc32c_generic(E) crc16(E) mbcache(E) jbd2(E) fscrypto(E) xhci_pci(E) sdhci_pci(E) cqhci(E) intel_lpss_pci(E) intel_lpss(E) crc32c_intel(E) xhci_hcd(E) sdhci(E) i2c_i801(E) e1000e(E) mmc_core(E) [73130.012218] ptp(E) pps_core(E) usbcore(E) mfd_core(E) sd_mod(E) fan(E) thermal(E) [73130.012227] CPU: 3 PID: 82 Comm: gvt workload 0 Tainted: G W E 5.0.0-rc7-staging-190226+ #282 [73130.012228] Hardware name: /NUC6i5SYB, BIOS SYSKLi35.86A.0039.2016.0316.1747 03/16/2016 [73130.012232] RIP: 0010:__list_add_valid+0x4d/0x70 [73130.012234] Code: c3 48 89 d1 48 c7 c7 e0 82 91 bb 48 89 c2 e8 44 8a cc ff 0f 0b 31 c0 c3 48 89 c1 4c 89 c6 48 c7 c7 30 83 91 bb e8 2d 8a cc ff <0f> 0b 31 c0 c3 48 89 f2 4c 89 c1 48 89 fe 48 c7 c7 80 83 91 bb e8 [73130.012236] RSP: 0018:ffffa4924107fdd0 EFLAGS: 00010286 [73130.012238] RAX: 0000000000000000 RBX: ffff995d8a5ccf00 RCX: 0000000000000006 [73130.012240] RDX: 0000000000000007 RSI: 0000000000000086 RDI: ffff995faad96680 [73130.012241] RBP: 0000000000000000 R08: 0000000000213a28 R09: 0000000000000084 [73130.012243] R10: 0000000000000000 R11: ffffa4924107fc70 R12: ffff995d8a5ccf78 [73130.012245] R13: ffff995f970c8000 R14: ffff995f0dc5bdf8 R15: ffff995f970cca50 [73130.012247] FS: 0000000000000000(0000) GS:ffff995faad80000(0000) knlGS:0000000000000000 [73130.012249] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [73130.012250] CR2: 00000222e1891000 CR3: 0000000116848002 CR4: 00000000003626e0 [73130.012252] Call Trace: [73130.012258] intel_vgpu_pin_mm+0x7a/0xa0 [73130.012262] workload_thread+0x683/0x12a0 [73130.012266] ? do_wait_intr_irq+0xb0/0xb0 [73130.012269] ? finish_wait+0x80/0x80 [73130.012271] ? intel_vgpu_clean_workloads+0x110/0x110 [73130.012274] kthread+0x116/0x130 [73130.012276] ? kthread_bind+0x30/0x30 [73130.012280] ret_from_fork+0x35/0x40 [73130.012285] WARNING: CPU: 3 PID: 82 at lib/list_debug.c:28 __list_add_valid+0x4d/0x70 [73130.012286] ---[ end trace 458a2e792eec21c0 ]--- v2: - simplify lock handling Reviewed-by: Xiong Zhang <xiong.y.zhang@intel.com> Cc: Xiong Zhang <xiong.y.zhang@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-11-07Merge tag 'gvt-fixes-2018-11-07' of https://github.com/intel/gvt-linux into ↵Joonas Lahtinen
drm-intel-fixes gvt-fixes-2018-11-07 - Fix invalidate of old ggtt entry (Hang) - Fix partial ggtt entry update in any order (Hang) - Fix one mask setting for chicken reg (Xinyun) - Fix eDP warning in guest (Longhe) Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> From: Zhenyu Wang <zhenyuw@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181107023137.GO25194@zhen-hp.sh.intel.com
2018-11-06drm/i915: Compare user's 64b GTT offset even on 32bChris Wilson
Beware mixing unsigned long constants and 64b values, as on 32b the constant will be zero extended and discard the high 32b when used as a mask! Reported-by: Sergii Romantsov <sergii.romantsov@globallogic.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108282 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: stable@vger.kernel.org Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181025091823.20571-2-chris@chris-wilson.co.uk (cherry picked from commit 6fc4e48f9ed46e9adff236a0c350074aafa3b7fa) Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2018-10-31drm/i915/gvt: support inconsecutive partial gtt entry writeHang Yuan
Previously we assumed two 4-byte writes to the same PTE coming in sequence. But recently we observed inconsecutive partial write happening as well. So this patch enhances the previous solution. It now uses a list to save more partial writes. If one partial write can be combined with another one in the list to construct a full PTE, update its shadow entry. Otherwise, save the partial write in the list. v2: invalidate old entry and flush ggtt (Zhenyu) v3: split old ggtt page unmap to another patch (Zhenyu) v4: refine codes (Zhenyu) Signed-off-by: Hang Yuan <hang.yuan@linux.intel.com> Cc: Yan Zhao <yan.y.zhao@intel.com> Cc: Xiaolin Zhang <xiaolin.zhang@intel.com> Cc: Zhenyu Wang <zhenyu.z.wang@intel.com> Reviewed-by: Xiaolin Zhang <xiaolin.zhang@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-07-30BackMerge v4.18-rc7 into drm-nextDave Airlie
rmk requested this for armada and I think we've had a few conflicts build up. Signed-off-by: Dave Airlie <airlied@redhat.com>
2018-07-09drm/i915/gvt: Add GTT clear_pse operationChangbin Du
Add clear_pse operation in case we need to split huge gtt into small pages. v2: correct description. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-07-09drm/i915/gvt: Add software PTE flag to mark special 64K splited entryChangbin Du
This add a software PTE flag on the Ignored bit of PTE. It will be used to identify splited 64K shadow entries. v2: fix mask definition. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-07-09drm/i915/gvt: Detect 64K gtt entry by IPS bit of PDEChangbin Du
This change help us detect the real entry type per PSE and IPS setting. For 64K entry, we also need to check reg GEN8_GAMW_ECO_DEV_RW_IA. v2: Extend IPS mmio control to Gen10. (Matthew Auld) Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-07-09drm/i915/gvt: Add PTE IPS bit operationsChangbin Du
Add three IPS operation functions to test/set/clear IPS in PDE. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-07-09drm/i915/gvt: Add new 64K entry typeChangbin Du
Add a new entry type GTT_TYPE_PPGTT_PTE_64K_ENTRY. 64K entry is very different from 2M/1G entry. 64K entry is controlled by IPS bit in upper PDE. To leverage the current logic, I take IPS bit as 'PSE' for PTE level. Which means, 64K entries can also processed by get_pse_type(). v2: Make it bisectable. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-07-02drm/i915/gvt: fix a bug of partially write ggtt entiesZhao Yan
when guest writes ggtt entries, it could write 8 bytes a time if gtt_entry_size is 8. But, qemu could split the 8 bytes into 2 consecutive 4-byte writes. If each 4-byte partial write could trigger a host ggtt write, it is very possible that a wrong combination is written to the host ggtt. E.g. the higher 4 bytes is the old value, but the lower 4 bytes is the new value, and this 8-byte combination is wrong but written to the ggtt, thus causing bugs. To handle this condition, we just record the first 4-byte write, then wait until the second 4-byte write comes and write the combined 64-bit data to host ggtt table. To save memory space and to spot partial write as early as possible, we don't keep this information for every ggtt index. Instread, we just record the last ggtt write position, and assume the two 4-byte writes come in consecutively for each vgpu. This assumption is right based on the characteristic of ggtt entry which stores memory address. When gtt_entry_size is 8, the guest memory physical address should be 64 bits, so any sane guest driver should write 8-byte long data at a time, so 2 consecutive 4-byte writes at the same ggtt index should be trapped in gvt. v2: when incomplete ggtt entry write is located, e.g. 1. guest only writes 4 bytes at a ggtt offset and no long writes the rest 4 bytes. 2. guest writes 4 bytes of a ggtt offset, then write at other ggtt offsets, then return back to write the left 4 bytes of the first ggtt offset. add error handling logic to remap host entry to scratch page, and mark guest virtual ggtt entry as not present. (zhenyu wang) Signed-off-by: Zhao Yan <yan.y.zhao@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-30drm/i915/gvt: Cancel dma map when resetting ggtt entriesChangbin Du
Ditto, don't forget ggtt entries during reset. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-19drm/i915/gvt: Invalidate vGPU PPGTT mm objects during a vGPU reset.Zhi Wang
As different OSes might handling GVT PPGTT creation/destroy notification differently during a vGPU reset. A better approach is invalidating all vGPU PPGTT mm objects during vGPU reset. Signed-off-by: Zhi Wang <zhi.a.wang@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-06drm/i915/gvt: Manage shadow pages with radix treeChangbin Du
We don't know how many page tables will be shadowed. It varies considerably corresponding to guest load. Radix tree is a better choice for us. Since Page Frame Number is used as key so most of the bits are common. Here is some performance data (duration in us) of looking up a element: Before: (aka. ppgtt_find_shadow_page) 0.308 0.292 0.246 0.432 0.143 ... 0.311 0.225 0.382 0.199 0.325 After: (aka. intel_vgpu_find_spt_by_mfn) 0.106 0.106 0.107 0.106 0.105 0.107 ... 0.107 0.109 0.105 0.108 This time I didn't get the early data of hash table. The data is measured when desktop is shown. As last change, the overall benchmark almost is not changed, but we get better scalability. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-06drm/i915/gvt: Provide generic page_track infrastructure for write-protected pageChangbin Du
This patch provide generic page_track infrastructure for write-protected guest page. The old page_track logic gets rewrote and now stays in a new standalone page_track.c. This page track infrastructure can be both used by vGUC and GTT shadowing. The important change is that it uses radix tree instead of hash table. We don't have a predictable number of pages that will be tracked. Here is some performance data (duration in us) of looking up a element: Before: (aka. intel_vgpu_find_tracked_page) 0.091 0.089 0.090 ... 0.093 0.091 0.087 ... 0.292 0.285 0.292 0.291 After: (aka. intel_vgpu_find_page_track) 0.104 0.105 0.100 0.102 0.102 0.100 ... 0.101 0.101 0.105 0.105 The hash table has good performance at beginning, but turns bad with more pages being tracked even no 3D applications are running. As expected, radix tree has stable duration and very quick. The overall benchmark (tested with Heaven Benchmark) marginally improved since this is not the bottleneck. What we benefit more from this change is scalability. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-06drm/i915/gvt: Rename shadow_page to short name sptChangbin Du
The target structure of some functions is struct intel_vgpu_ppgtt_spt and their names are xxx_shadow_page. It should be xxx_shadow_page_table. Let's use short name 'spt' instead to reduce the length. As well as the hash table name. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-06drm/i915/gvt: Rework shadow page management codeChangbin Du
This is a another big one and the GVT shadow page management code is heavily refined. The new code only use struct intel_vgpu_ppgtt_spt to represent a vgpu shadow page table - w/ or wo/ a guest page associated with. A pure shadow page (no guest page associated) will be used to shadow splited 2M huge gtt. In this case, the spt.guest_page.gfn should be a zero. To search a existed shadow page table, we have two new interfaces: - intel_vgpu_find_spt_by_gfn(), find a spt by guest gfn. It must not be a pure spt. - intel_vgpu_find_spt_by_mfn, Find the spt using shadow page mfn in shadowed PTE. The oos_page management is remained as what is was. v2: Split some changes into small standalone patches. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-06drm/i915/gvt: Factor out intel_vgpu_{get, put}_ppgtt_mm interfaceChangbin Du
Factor out these two interfaces so we can kill some duplicated code in scheduler.c. v2: - rename to intel_vgpu_{get,put}_ppgtt_mm - refine handle_g2v_notification Signed-off-by: Changbin Du <changbin.du@intel.com> Reviewed-by: Zhi Wang <zhi.a.wang@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-06drm/i915/gvt: Rename ggtt related functions to be more specificChangbin Du
Accurate names help to avoid confusing so improve readability. Signed-off-by: Changbin Du <changbin.du@intel.com> Reviewed-by: Zhi Wang <zhi.a.wang@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-06drm/i915/gvt: Refine ggtt and ppgtt root entry opsChangbin Du
Separate ggtt and ppgtt since they are different. A little more code but straightforward. And move these helpers to gtt.c since that is the only client. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-06drm/i915/gvt: Refine the intel_vgpu_mm reference managementChangbin Du
If we manage an object with a reference count, then its life cycle must flow the reference count operations. Meanwhile, change the operation functions to generic name *put* and *get*. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2018-03-06drm/i915/gvt: Rework shadow graphic memory management codeChangbin Du
This is a big one and the GVT shadow graphic memory management code is heavily refined. The new code is more straightforward with less code. The struct intel_vgpu_mm is restructured to be clearly defined, use accurate names and some of the original fields are removed which are really redundant. Now we only manage ppgtt mm object with mm->ppgtt_mm.lru_list. No need to mix ppgtt and ggtt together, since one vGPU only has one ggtt object. v4: Don't invoke ppgtt_free_all_shadow_page before intel_vgpu_destroy_all_ppgtt_mm. v3: Add GVT_RING_CTX_NR_PDPS to avoid confusing about the PDPs. v2: Split some changes into small standalone patches. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2017-12-22drm/i915/gvt: move write protect handler out of mmio emulation functionZhenyu Wang
It's a bit confusing that page write protect handler is live in mmio emulation handler. This moves it to stand alone gvt ops. Also remove unnecessary check of write protected page access in mmio read handler and cleanup handling of failsafe case. v2: rebase Reviewed-by: Xiong Zhang <xiong.y.zhang@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2017-11-16Revert "drm/i915/gvt: Refine broken PPGTT scratch"Zhenyu Wang
This reverts commit b20d09886fd1b74cd2255d846029a049e524db14. This caused windows driver boot errors for invalid page address. Revert for now. Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2017-11-16drm/i915/gvt: Refine broken PPGTT scratchZhi Wang
Refine previously broken PPGTT scratch. Scratch PTE was no correctly handled and also the handling of scratch entries in page table walk was not well organized, which brings gaps of introducing lazy shadow. Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
2017-11-16drm/i915/gvt: Introduce ops->set_present()Zhi Wang
We need ops->set_present() during generating a new scratch page table entry. Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
2017-11-16drm/i915/gvt: Let the caller choose if a shadow page should be put into hash ↵Zhi Wang
table As we want to re-use intel_vgpu_shadow_page in buidling scrach page table and we don't want to put scrach page table page into hash table, a new param is introduced to give the caller a choice to decide if a shadow page should be put into hash table. Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
2017-11-16drm/i915/gvt: Use I915_GTT_PAGE_SIZEZhi Wang
As there is already an I915_GTT_PAGE_SIZE marco in i915, let GVT-g use it as well. Also this patch re-names some GTT marcos with additional prefix. Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
2017-11-16drm/i915/gvt: Factor intel_vgpu_page_trackZhi Wang
As the data structure of "intel_vgpu_guest_page" will become much heavier in future, it's better to factor out the guest memory page track mechnisim as early as possible. Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
2017-08-10drm/i915/gvt: Refine the intel_vgpu_reset_gtt reset functionChuanxiao Dong
When doing the VGPU reset, we don't need to do the gtt/ppgtt reset. This will make the GVT to do the ppgtt shadow every time for a workload and caused really bad performance after a VGPU reset. This patch will make sure ppgtt clean only happen at device module level reset to fix this. Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2017-08-10drm/i915/gvt: Add carefully checking in GTT walker pathsChangbin Du
When debugging the gtt code, found the intel_vgpu_gma_to_gpa() can translate any given GMA though the GMA is not valid. This because the GTT ops suppress the possible errors, which may result in an invalid PT entry is retrieved by upper caller. This patch changed the prototype of pte ops to propagate status to callers. Then we make sure the GTT walker stop as early as when a error is detected to prevent undefined behavior. Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2017-01-13drm/i915/gvt: introuduce intel_vgpu_reset_gtt() to reset gttChangbin Du
This patch introduces a new function intel_vgpu_reset_gtt() to reset the all GTT related status, including GGTT, PPGTT, scratch page. This function can free all shadowed PPGTT, clear all GGTT entry, and clear scratch page to all zero. After this, we can ensure no gtt related information can be leakaged from one VM to anothor one when assign vgpu instance across different VMs (not simultaneously). Signed-off-by: Changbin Du <changbin.du@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2016-12-26drm/i915/gvt: reset the GGTT entry when vGPU createdPing Gao
The GGTT space is partitioned between vGPUs, it could be reused by next vGPU after previous one is release, the stale entries need point to scratch page when vGPU created. v2: Reset logic move to vGPU create. v3: Correct the commit msg. v4: Move the reset function to vGPU init gtt function, as result it's no need explicitly in vGPU reset logic as vGPU init gtt called during reset. Signed-off-by: Ping Gao <ping.a.gao@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2016-11-07drm/i915/gvt: implement scratch page table tree for shadow PPGTTPing Gao
All the unused entries in the page table tree(PML4E->PDPE->PDE->PTE) should point to scratch page table/scratch page to avoid page walk error due to the page prefetching. When removing an entry in shadow PPGTT, it need map to scratch page also, the older implementation use single scratch page to assign to all level entries, it doesn't align the page walk behavior when removed entry is in PML, PDP, PD. To avoid potential page walk error this patch implement a scratch page tree to replace the single scratch page. v2: more details in commit message address Kevin's comments. Signed-off-by: Ping Gao <ping.a.gao@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2016-10-14drm/i915/gvt: vGPU graphics memory virtualizationZhi Wang
The vGPU graphics memory emulation framework is responsible for graphics memory table virtualization. Under virtualization environment, a VM will populate the page table entry with guest page frame number(GPFN/GFN), while HW needs a page table filled with MFN(Machine frame number). The relationship between GFN and MFN(Machine frame number) is managed by hypervisor, while GEN HW doesn't have such knowledge to translate a GFN. To solve this gap, shadow GGTT/PPGTT page table is introdcued. For GGTT, the GFN inside the guest GGTT page table entry will be translated into MFN and written into physical GTT MMIO registers when guest write virtual GTT MMIO registers. For PPGTT, a shadow PPGTT page table will be created and write-protected translated from guest PPGTT page table. And the shadow page table root pointers will be written into the shadow context after a guest workload is shadowed. vGPU graphics memory emulation framework consists: - Per-GEN HW platform page table entry bits extract/de-extract routines. - GTT MMIO register emulation handlers, which will call hypercall to do GFN->MFN translation when guest write GTT MMIO register - PPGTT shadow page table routines, e.g. shadow create/destroy/out-of-sync Signed-off-by: Zhi Wang <zhi.a.wang@intel.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>