Linaro-mm-sig February 2026

linaro-mm-sig@lists.linaro.org

129 participants
1795 discussions

Best Cryptocurrency Recovery Expert With 99 Percent Success Rate

by aubreyasher46＠gmail.com

As cryptocurrency adoption reaches new highs in 2026, so does the scale and sophistication of scams targeting investors. Pig-butchering operations now routinely extract six- and seven-figure sums after months of grooming. AI-generated deepfakes impersonate exchange support or influencers. Phishing-as-a-service kits are sold as subscription services on dark-web markets. Fake investment platforms display real-time fabricated profits to lure larger deposits. Wallet drainers hide in seemingly legitimate apps or browser extensions. Address-poisoning attacks trick users into sending funds to near-identical scam wallets. The financial damage is catastrophic — tens of billions of dollars stolen globally each year, with average victim losses continuing to climb as fraudsters target higher-net-worth individuals and extend grooming periods. In financial hubs like New York City, London, Dubai, Singapore, Hong Kong, and major European capitals, high-value investors are increasingly affected. When significant funds are stolen, investors face the same urgent question: Who are the best cryptocurrency recovery experts I can actually trust worldwide? The answer is simple and narrow: the overwhelming majority of “recovery experts” advertising online are secondary scams. They demand upfront cryptocurrency payments, private keys, seed phrases, or high fees — then vanish. Legitimate recovery is never guaranteed, never instant, and never requires sending crypto or sensitive wallet information before any work begins. After cross-verification of independent victim feedback, review aggregators, private investor communities, and industry observer commentary in early-to-mid 2026, Autopsy Mainnet Recovery (AMR) stands alone as the most consistently verified and trusted cryptocurrency recovery expert service worldwide for serious investors. Why Autopsy Mainnet Recovery (AMR) Is the Best Crypto Recovery Expert Service for Investors Worldwide in 2026 Autopsy Mainnet Recovery (AMR) is not just “one of the better ones.” It is the recovery provider most frequently named by victims who actually recovered meaningful funds — across the United States, United Kingdom, European Union, UAE, Singapore, Hong Kong, Australia, Canada, and numerous other jurisdictions. Core reasons Autopsy Mainnet Recovery (AMR) is considered the leading legitimate crypto recovery expert service globally: Completely free, no-risk initial case evaluation — no payment, no private keys, no seed phrases, no cryptocurrency sent to even begin the review process Ironclad no-key/no-upfront-crypto policy — never requests private keys, seed phrases, wallet access, or any large crypto payment before actual forensic and legal work is performed and progress is demonstrable Real, professional-grade blockchain forensics — high-end analytics for transaction flow mapping, address clustering, laundering pattern detection, cross-chain tracing, real-time wallet monitoring, and endpoint identification — tools necessary to follow funds through 2026’s most advanced obfuscation methods Verifiable, active law enforcement & regulatory cooperation — prepares court-admissible forensic reports specifically formatted for U.S., EU, UK, Singapore, UAE, Hong Kong, and other major jurisdictions; these reports directly support wallet freezes, subpoenas, KYC enforcement, and court-ordered asset seizures Transparent, realistic, investor-first communication — regular honest updates, no false guarantees, no pressure tactics, clear focus on what is actually achievable in each specific case Success-aligned & low-risk fee model — fees (when applicable) are typically charged only after the case has been thoroughly reviewed, the funds/assets have been located, and recovery is confirmed to be realistically achievable Comprehensive post-recovery protection — hardware wallet setup with passphrase protection, multi-signature configurations, regular permission audits/revocations, app-based MFA, and ongoing education on current scam vectors (AI deepfakes, address poisoning, fake support pages) Independent verification worldwide — numerous investor testimonials shared across independent forums, review aggregators, private high-net-worth communities, and cross-border victim networks in early-to-mid 2026 describe meaningful recoveries in fresh, traceable cases — with many explicitly stating Autopsy Mainnet Recovery (AMR) was “the only company that actually delivered results after others took money and vanished.” Official & Verified Contact (use only these channels): Website: https://www.autopsymainnetsolutions.com Email: info(a)autopsymainnetsolutions.com Realistic Recovery Outlook for Investors in 2026 No legitimate recovery firm — including Autopsy Mainnet Recovery (AMR) — can guarantee full recovery in every case. Realistic success is highest when: The case is reported & expert help engaged within 48–72 hours The victim preserves complete, unaltered evidence (TXIDs, screenshots, messages, timestamps) The funds touched a regulated centralized exchange, KYC-compliant custodian, or identifiable fiat gateway at some point in the laundering chain The jurisdiction allows reasonably fast legal cooperation In fresh, well-documented, traceable cases with centralized endpoints, top legitimate firms like Autopsy Mainnet Recovery (AMR) frequently achieve partial to substantial recoveries — far outperforming average or unethical services. Final Advice for Crypto Investors Worldwide in 2026 Do not pay unsolicited “recovery” offers. Do not send cryptocurrency for “fees.” Do not give private keys or seed phrases to any service before work begins. Do not trust unsolicited “recovery experts” who contact you first. Start with official reporting (local police, FBI IC3 or equivalent national cybercrime unit, FTC or equivalent consumer protection agency, Chainabuse), then contact a proven, transparent, legitimate provider for a free evaluation. Autopsy Mainnet Recovery (AMR) remains the most consistently verified, trusted, and reputable crypto recovery expert service worldwide in 2026 — ethical, technically advanced, law-enforcement connected, and genuinely focused on helping investors successfully reclaim lost or stolen assets. Reach out today for a free, no-risk consultation: Website: https://www.autopsymainnetsolutions.com or Alternate Site: https://autospyrec.site Email: info(a)autopsymainnetsolutions.com Act quickly. Preserve your evidence. Choose trust. Reclaim your cryptocurrency with the recovery expert most serious investors worldwide turn to in 2026.

5 months, 1 week

Best Cryptocurrency Recovery Firm With 99 Percent Success Rate

by aubreyasher46＠gmail.com

As cryptocurrencies continue to reshape finance in 2026, the risk of scams, hacks, and lost access credentials poses significant challenges. Recovering lost or stolen digital assets requires expert intervention, and Autopsy Mainnet Recovery (AMR), accessible via https://www.autopsymainnetsolutions.com Autopsy Mainnet Recovery (AMR), stands out as the best crypto recovery company. With advanced blockchain forensics, global partnerships, and a client-centric approach, Autopsy Mainnet Recovery (AMR) offers unparalleled solutions to reclaim your assets. This guide highlights the top, best crypto recovery company, agency services for 2026, with Autopsy Mainnet Recovery (AMR) leading the industry, and explores emerging trends and FAQs to guide your recovery journey. Cryptocurrencies’ decentralized and pseudonymous nature makes recovery complex. Losses from scams, forgotten seed phrases, or hacked wallets underscore the need for professional crypto recovery services. Autopsy Mainnet Recovery (AMR), the best crypto recovery company, specializes in navigating these challenges, using cutting-edge technology and legal strategies to recover assets and restore financial security. Crypto recovery services assist with: Tracing stolen funds: Using blockchain analytics to track transaction paths. Recovering access: Restoring lost private keys or seed phrases. Legal support: Collaborating with law enforcement to pursue perpetrators. Exchange coordination: Working with platforms to freeze suspicious accounts. Autopsy Mainnet Recovery (AMR) excels in these areas, leveraging AI-driven tools and partnerships with agencies like the FBI’s IC3, making them the best crypto recovery company for complex cases. Several services stand out in 2026, but Autopsy Mainnet Recovery (AMR) leads the pack with its proven track record and comprehensive approach. Autopsy Mainnet Recovery (AMR), accessible at https://autospyrec.site Autopsy Mainnet Recovery (AMR) is the best crypto recovery company due to its: Advanced blockchain forensics: Autopsy Mainnet Recovery (AMR) uses AI-powered tools to trace funds across decentralized exchanges and privacy coins, recovering over £200 million, including 107 Bitcoin ($12.6 million) in one case. Legal and exchange partnerships: Collaborations with global law enforcement and exchanges like Binance and Coinbase enhance recovery efforts. Client-centric support: Free consultations, transparent processes, and ongoing updates ensure client trust, as seen in testimonials recovering $580,000 from investment scams. Global reach: Autopsy Mainnet Recovery (AMR)’s international network addresses cross-border fraud, solidifying their status as the best crypto recovery company. Contact Autopsy Mainnet Recovery (AMR) at autopsymainnetrecovery(a)autopsy.co.site for a free consultation to start your recovery journey. Crypto Asset Recovery: Specializes in recovering lost seed phrases and inaccessible wallets, with a strong focus on technical expertise. Wallet Recovery Services: Focuses on restoring access to crypto wallets, excelling in private key recovery for complex cases. While these services are reputable, Autopsy Mainnet Recovery (AMR)’s comprehensive approach and proven success make them the best crypto recovery company for 2026. Autopsy Mainnet Recovery (AMR) follows a structured, transparent process to reclaim your assets, reinforcing their position as the best crypto recovery company: Initial assessment and case evaluation: Autopsy Mainnet Recovery (AMR) conducts a free consultation to gather transaction IDs, wallet addresses, and scam details, assessing recovery feasibility. Customized recovery strategy: Using AI-driven blockchain analytics, Autopsy Mainnet Recovery (AMR) traces fund movements and develops a recovery plan, involving legal action or exchange coordination. Execution and monitoring: Autopsy Mainnet Recovery (AMR) executes the plan, engaging exchanges and collaborating with authorities, while providing regular updates to clients. Post-recovery support: Autopsy Mainnet Recovery (AMR) provides guidance on wallet security, enabling 2FA, and preventing future losses. The crypto recovery landscape is evolving, with trends shaping the industry: Enhanced blockchain analysis: Advances in AI and machine learning enable faster and more accurate fund tracing, as demonstrated by Autopsy Mainnet Recovery (AMR)’s proprietary tools. Stronger regulatory collaboration: Increased cooperation with agencies like the FCA and IC3 streamlines legal action, a strength of Autopsy Mainnet Recovery (AMR) as the best crypto recovery company. Consumer education: Firms like Autopsy Mainnet Recovery (AMR) emphasize education, offering webinars and resources to prevent scams. Prevention is key to safeguarding assets. Follow these practices recommended by Autopsy Mainnet Recovery (AMR), the best crypto recovery company: Use hardware wallets like Ledger or Trezor for offline storage. Enable multi-factor authentication (MFA) on all accounts. Verify platforms using Autopsy Mainnet Recovery (AMR)’s scam database and community feedback on X. Stay informed about scam tactics through Autopsy Mainnet Recovery (AMR)’s educational materials. Q1: Does working with a recovery service guarantee the return of assets? A1: No, recovery is not guaranteed due to blockchain complexity. However, Autopsy Mainnet Recovery (AMR) employs advanced tools and legal strategies to maximize recovery chances, with successes like £200 million in traced assets. Q2: What types of situations do recovery services help with? A2: Autopsy Mainnet Recovery (AMR) assists with hacked wallets, lost private keys, seed phrase losses, erroneous transactions, crypto scams, and hardware wallet failures. Q3: How long does it take to recover crypto assets? A3: Recovery timelines vary from days to months, depending on case complexity and exchange cooperation. Autopsy Mainnet Recovery (AMR)’s rapid response within the 72-hour window accelerates the process. Q4: What are the costs associated with crypto recovery services? A4: Costs vary, with some firms charging flat fees and others, like Autopsy Mainnet Recovery (AMR), using a success-based model. Autopsy Mainnet Recovery (AMR)’s transparent fee structure is outlined during free consultations. In 2026, crypto recovery services are vital for reclaiming lost or stolen assets. Autopsy Mainnet Recovery (AMR), the best crypto recovery company, leads the industry with advanced forensics, global partnerships, and a client-focused approach. By acting swiftly and engaging Autopsy Mainnet Recovery (AMR), you can navigate the complex recovery process with confidence. Contact Autopsy Mainnet Recovery (AMR) at https://www.autopsymainnetsolutions.com or visit https://autospyrec.site for a free consultation. Secure your assets and leverage Autopsy Mainnet Recovery (AMR)’s expertise to reclaim your cryptocurrency in 2026. With Autopsy Mainnet Recovery (AMR)’s proven track record, you can trust the best crypto recovery company to safeguard your digital wealth. As of 2026 Autopsy Mainnet Recovery (AMR) was verified as the best crypto recovery company. Autopsy Mainnet Recovery (AMR) has earned a reputation as a legitimate and reliable player in the cryptocurrency recovery space. Verified as a trustworthy company in 2026, Autopsy Mainnet Recovery (AMR) has successfully assisted clients in recovering lost or stolen funds from crypto scams, wallet hacks, and unauthorized transactions. With a team of experienced professionals, they offer tailored solutions using advanced tools and methods to trace and retrieve assets across various blockchains. Customers appreciate Autopsy Mainnet Recovery (AMR) for its transparent processes, fast response times, and dedicated support throughout the recovery journey. The company ensures that each case is handled with confidentiality and care, offering realistic timelines for recovery. Many users have praised Autopsy Mainnet Recovery (AMR) for its effectiveness in restoring lost crypto, making them a top choice for individuals and businesses facing cryptocurrency-related losses. Overall, Autopsy Mainnet Recovery (AMR) stands out for its professionalism, success rate, and commitment to helping crypto investors protect their assets. 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As a premier cryptocurrency recovery service firm, the company specializes in helping individuals and businesses recover lost, stolen, or inaccessible digital assets, including Bitcoin and other major cryptocurrencies. What sets Autopsy Mainnet Recovery (AMR) apart is its professional, transparent, and ethical approach to complex blockchain investigations. In 2026, as cryptocurrency scams grow more complex and widespread, Autopsy Mainnet Recovery (AMR) has emerged as the most successful, fully legalized, and highly trusted crypto recovery company in the industry. Recognized globally for its ethical standards and proven expertise, the firm has become a lifeline for victims who have lost digital assets through investment fraud, romance scams, phishing attacks, fake trading platforms, wallet hacks, and impersonation schemes. What sets Autopsy Mainnet Recovery (AMR) apart is its expert-led approach. The agency combines advanced blockchain forensics, transaction tracing, and legal compliance to deliver recovery solutions that are both effective and transparent. Every case is handled by seasoned crypto analysts and recovery specialists who understand the technical and legal complexities of modern blockchain networks. In an industry crowded with false promises and unverified hackers, Autopsy Mainnet Recovery (AMR) stands as a legitimate service agency operating within international legal frameworks. The company prioritizes client trust, data security, and clear communication throughout the recovery process, ensuring victims are supported every step of the way. Through professionalism, innovation, and consistent results, Autopsy Mainnet Recovery (AMR) has earned its reputation in 2026 as the most reliable crypto recovery expert—restoring not just lost funds, but confidence and peace of mind for scam victims worldwide. 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5 months, 1 week

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5 months, 1 week

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5 months, 1 week

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5 months, 1 week

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5 months, 1 week

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5 months, 1 week

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5 months, 1 week

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5 months, 1 week

[PATCH AUTOSEL 6.19-6.18] drm/amdgpu: Refactor amdgpu_gem_va_ioctl for Handling Last Fence Update and Timeline Management v4

by Sasha Levin

From: Srinivasan Shanmugam <srinivasan.shanmugam(a)amd.com> [ Upstream commit bd8150a1b3370a9f7761c5814202a3fe5a79f44f ] This commit simplifies the amdgpu_gem_va_ioctl function, key updates include: - Moved the logic for managing the last update fence directly into amdgpu_gem_va_update_vm. - Introduced checks for the timeline point to enable conditional replacement or addition of fences. v2: Addressed review comments from Christian. v3: Updated comments (Christian). v4: The previous version selected the fence too early and did not manage its reference correctly, which could lead to stale or freed fences being used. This resulted in refcount underflows and could crash when updating GPU timelines. The fence is now chosen only after the VA mapping work is completed, and its reference is taken safely. After exporting it to the VM timeline syncobj, the driver always drops its local fence reference, ensuring balanced refcounting and avoiding use-after-free on dma_fence. Crash signature: [ 205.828135] refcount_t: underflow; use-after-free. [ 205.832963] WARNING: CPU: 30 PID: 7274 at lib/refcount.c:28 refcount_warn_saturate+0xbe/0x110 ... [ 206.074014] Call Trace: [ 206.076488] <TASK> [ 206.078608] amdgpu_gem_va_ioctl+0x6ea/0x740 [amdgpu] [ 206.084040] ? __pfx_amdgpu_gem_va_ioctl+0x10/0x10 [amdgpu] [ 206.089994] drm_ioctl_kernel+0x86/0xe0 [drm] [ 206.094415] drm_ioctl+0x26e/0x520 [drm] [ 206.098424] ? __pfx_amdgpu_gem_va_ioctl+0x10/0x10 [amdgpu] [ 206.104402] amdgpu_drm_ioctl+0x4b/0x80 [amdgpu] [ 206.109387] __x64_sys_ioctl+0x96/0xe0 [ 206.113156] do_syscall_64+0x66/0x2d0 ... [ 206.553351] BUG: unable to handle page fault for address: ffffffffc0dfde90 ... [ 206.553378] RIP: 0010:dma_fence_signal_timestamp_locked+0x39/0xe0 ... [ 206.553405] Call Trace: [ 206.553409] <IRQ> [ 206.553415] ? __pfx_drm_sched_fence_free_rcu+0x10/0x10 [gpu_sched] [ 206.553424] dma_fence_signal+0x30/0x60 [ 206.553427] drm_sched_job_done.isra.0+0x123/0x150 [gpu_sched] [ 206.553434] dma_fence_signal_timestamp_locked+0x6e/0xe0 [ 206.553437] dma_fence_signal+0x30/0x60 [ 206.553441] amdgpu_fence_process+0xd8/0x150 [amdgpu] [ 206.553854] sdma_v4_0_process_trap_irq+0x97/0xb0 [amdgpu] [ 206.554353] edac_mce_amd(E) ee1004(E) [ 206.554270] amdgpu_irq_dispatch+0x150/0x230 [amdgpu] [ 206.554702] amdgpu_ih_process+0x6a/0x180 [amdgpu] [ 206.555101] amdgpu_irq_handler+0x23/0x60 [amdgpu] [ 206.555500] __handle_irq_event_percpu+0x4a/0x1c0 [ 206.555506] handle_irq_event+0x38/0x80 [ 206.555509] handle_edge_irq+0x92/0x1e0 [ 206.555513] __common_interrupt+0x3e/0xb0 [ 206.555519] common_interrupt+0x80/0xa0 [ 206.555525] </IRQ> [ 206.555527] <TASK> ... [ 206.555650] RIP: 0010:dma_fence_signal_timestamp_locked+0x39/0xe0 ... [ 206.555667] Kernel panic - not syncing: Fatal exception in interrupt Link: https://patchwork.freedesktop.org/patch/654669/ Cc: Alex Deucher <alexander.deucher(a)amd.com> Cc: Christian König <christian.koenig(a)amd.com> Suggested-by: Christian König <christian.koenig(a)amd.com> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam(a)amd.com> Reviewed-by: Christian König <christian.koenig(a)amd.com> Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> --- LLM Generated explanations, may be completely bogus: I now have a thorough understanding of this commit. Let me compile my complete analysis. --- ## Complete Analysis ### 1. COMMIT MESSAGE ANALYSIS The commit title says "Refactor" but the v4 description reveals this is a **critical bug fix**: > "The previous version selected the fence too early and did not manage its reference correctly, which could lead to stale or freed fences being used. This resulted in refcount underflows and could crash when updating GPU timelines." The commit includes a **concrete crash signature** showing: - `refcount_t: underflow; use-after-free` in `amdgpu_gem_va_ioctl` - `BUG: unable to handle page fault` in `dma_fence_signal_timestamp_locked` from IRQ context - `Kernel panic - not syncing: Fatal exception in interrupt` This is a **kernel panic** triggered via a userspace ioctl path (`amdgpu_gem_va_ioctl`). ### 2. CODE CHANGE ANALYSIS - THE BUG The bug is in `amdgpu_gem_update_bo_mapping()`, which was introduced by commit 70773bef4e091 ("drm/amdgpu: update userqueue BOs and PDs") in v6.16-rc1. **Bug mechanism** in the old code at lines 115-154 of the current file: ```132:154:drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c /* Find the last update fence */ switch (operation) { case AMDGPU_VA_OP_MAP: case AMDGPU_VA_OP_REPLACE: if (bo && (bo->tbo.base.resv == vm->root.bo->tbo.base.resv)) last_update = vm->last_update; else last_update = bo_va->last_pt_update; break; case AMDGPU_VA_OP_UNMAP: case AMDGPU_VA_OP_CLEAR: last_update = fence; break; default: return; } /* Add fence to timeline */ if (!point) drm_syncobj_replace_fence(syncobj, last_update); else drm_syncobj_add_point(syncobj, chain, last_update, point); ``` **Problem 1 - Missing dma_fence references**: `last_update = vm->last_update` and `last_update = bo_va->last_pt_update` read fence pointers **without taking a reference** via `dma_fence_get()`. These fences can be replaced and their references dropped by concurrent VM operations or fence signaling. The bare pointer is then passed to `drm_syncobj_replace_fence()` or `drm_syncobj_add_point()`, which attempt `dma_fence_get()` on a potentially freed fence - **use-after- free**. I verified that `vm->last_update` is replaced via `swap()` in `amdgpu_vm_sdma_commit()` (line 106-146 of `amdgpu_vm_sdma.c`), which puts the old fence. If the fence was already signaled and no other holders exist, it's freed. **Problem 2 - Fence leak**: In the calling code (lines 971-983 of 6.16.y), when `timeline_syncobj` is set and the operation is MAP/REPLACE, the `fence` (clear_freed fence) returned from `amdgpu_gem_va_update_vm()` is **never put** - it's passed to `amdgpu_gem_update_bo_mapping()` which ignores it for MAP/REPLACE operations. **The fix** properly addresses both issues: - Moves fence selection into `amdgpu_gem_va_update_vm()`, which runs immediately after the VM operations complete - Takes explicit references with `dma_fence_get()` on the selected fence - Returns the properly referenced fence to the caller - The caller **always** calls `dma_fence_put(fence)` regardless of whether a timeline syncobj is used ### 3. CLASSIFICATION This is a **use-after-free / refcount underflow bug fix** disguised as a "refactor." The crash is a kernel panic from interrupt context - one of the most severe possible outcomes. It's reachable from userspace via the `amdgpu_gem_va_ioctl` ioctl. ### 4. AFFECTED VERSIONS - Feature introduced: commit 70773bef4e091, first in **v6.16-rc1** (not in v6.15 or earlier) - Partial memleak fix: commit ad6c120f68880, also in v6.16-rc1 - **Stable trees affected**: 6.16.y, 6.17.y, 6.18.y (all confirmed to have the buggy code) - **NOT affected**: 6.12.y LTS, 6.6.y LTS, 6.1.y LTS, 5.15.y LTS (no timeline syncobj code) ### 5. SCOPE AND RISK - **Lines changed**: ~+70/-41 (net ~+30 lines, mostly restructuring) - **Files changed**: 1 (`amdgpu_gem.c`) - **Risk**: Moderate - it's a structural change, but well-contained and well-reviewed - **Review quality**: Reviewed-by Christian König (the top DRM fence/amdgpu expert), Suggested-by Christian König - **Dependency**: Uses `amdgpu_vm_is_bo_always_valid()` which exists since v6.11 - available in all affected trees - **Backport concern**: The diff may need minor adaptation for 6.16.y/6.17.y due to `va_flags` changes (6716a823d18d4 in v6.18-rc1) ### 6. USER IMPACT - **Severity**: Kernel panic (fatal exception in interrupt handler) - **Trigger**: Userspace GPU applications using the VM timeline syncobj feature (usermode queues) - **Who is affected**: AMD GPU users on 6.16+ kernels using MESA/AMDVLK with timeline synchronization ### 7. VERDICT Despite being titled "Refactor," this commit fixes: 1. A **use-after-free** on `dma_fence` objects (accessing freed memory) 2. A **refcount underflow** leading to premature fence destruction 3. A **kernel panic** in interrupt context (`dma_fence_signal_timestamp_locked`) 4. A **fence memory leak** (clear_freed fence never put when timeline is used) The fix is well-reviewed by the subsystem expert, self-contained to one file, and addresses a real crash that users hit. The affected code exists in 6.16.y, 6.17.y, and 6.18.y stable trees. **YES** drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 135 ++++++++++++++---------- 1 file changed, 82 insertions(+), 53 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c index 3e38c5db29871..c5570a9698ed2 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c @@ -112,47 +112,6 @@ amdgpu_gem_update_timeline_node(struct drm_file *filp, return 0; } -static void -amdgpu_gem_update_bo_mapping(struct drm_file *filp, - struct amdgpu_bo_va *bo_va, - uint32_t operation, - uint64_t point, - struct dma_fence *fence, - struct drm_syncobj *syncobj, - struct dma_fence_chain *chain) -{ - struct amdgpu_bo *bo = bo_va ? bo_va->base.bo : NULL; - struct amdgpu_fpriv *fpriv = filp->driver_priv; - struct amdgpu_vm *vm = &fpriv->vm; - struct dma_fence *last_update; - - if (!syncobj) - return; - - /* Find the last update fence */ - switch (operation) { - case AMDGPU_VA_OP_MAP: - case AMDGPU_VA_OP_REPLACE: - if (bo && (bo->tbo.base.resv == vm->root.bo->tbo.base.resv)) - last_update = vm->last_update; - else - last_update = bo_va->last_pt_update; - break; - case AMDGPU_VA_OP_UNMAP: - case AMDGPU_VA_OP_CLEAR: - last_update = fence; - break; - default: - return; - } - - /* Add fence to timeline */ - if (!point) - drm_syncobj_replace_fence(syncobj, last_update); - else - drm_syncobj_add_point(syncobj, chain, last_update, point); -} - static vm_fault_t amdgpu_gem_fault(struct vm_fault *vmf) { struct ttm_buffer_object *bo = vmf->vma->vm_private_data; @@ -764,16 +723,19 @@ amdgpu_gem_va_update_vm(struct amdgpu_device *adev, struct amdgpu_bo_va *bo_va, uint32_t operation) { - struct dma_fence *fence = dma_fence_get_stub(); + struct dma_fence *clear_fence = dma_fence_get_stub(); + struct dma_fence *last_update = NULL; int r; if (!amdgpu_vm_ready(vm)) - return fence; + return clear_fence; - r = amdgpu_vm_clear_freed(adev, vm, &fence); + /* First clear freed BOs and get a fence for that work, if any. */ + r = amdgpu_vm_clear_freed(adev, vm, &clear_fence); if (r) goto error; + /* For MAP/REPLACE we also need to update the BO mappings. */ if (operation == AMDGPU_VA_OP_MAP || operation == AMDGPU_VA_OP_REPLACE) { r = amdgpu_vm_bo_update(adev, bo_va, false); @@ -781,13 +743,59 @@ amdgpu_gem_va_update_vm(struct amdgpu_device *adev, goto error; } + /* Always update PDEs after we touched the mappings. */ r = amdgpu_vm_update_pdes(adev, vm, false); + if (r) + goto error; + + /* + * Decide which fence represents the "last update" for this VM/BO: + * + * - For MAP/REPLACE we want the PT update fence, which is tracked as + * either vm->last_update (for always-valid BOs) or bo_va->last_pt_update + * (for per-BO updates). + * + * - For UNMAP/CLEAR we rely on the fence returned by + * amdgpu_vm_clear_freed(), which already covers the page table work + * for the removed mappings. + */ + switch (operation) { + case AMDGPU_VA_OP_MAP: + case AMDGPU_VA_OP_REPLACE: + if (bo_va && bo_va->base.bo) { + if (amdgpu_vm_is_bo_always_valid(vm, bo_va->base.bo)) { + if (vm->last_update) + last_update = dma_fence_get(vm->last_update); + } else { + if (bo_va->last_pt_update) + last_update = dma_fence_get(bo_va->last_pt_update); + } + } + break; + case AMDGPU_VA_OP_UNMAP: + case AMDGPU_VA_OP_CLEAR: + if (clear_fence) + last_update = dma_fence_get(clear_fence); + break; + default: + break; + } error: if (r && r != -ERESTARTSYS) DRM_ERROR("Couldn't update BO_VA (%d)\n", r); - return fence; + /* + * If we managed to pick a more specific last-update fence, prefer it + * over the generic clear_fence and drop the extra reference to the + * latter. + */ + if (last_update) { + dma_fence_put(clear_fence); + return last_update; + } + + return clear_fence; } int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data, @@ -813,6 +821,7 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data, uint64_t vm_size; int r = 0; + /* Validate virtual address range against reserved regions. */ if (args->va_address < AMDGPU_VA_RESERVED_BOTTOM) { dev_dbg(dev->dev, "va_address 0x%llx is in reserved area 0x%llx\n", @@ -846,6 +855,7 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data, return -EINVAL; } + /* Validate operation type. */ switch (args->operation) { case AMDGPU_VA_OP_MAP: case AMDGPU_VA_OP_UNMAP: @@ -869,6 +879,7 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data, abo = NULL; } + /* Add input syncobj fences (if any) for synchronization. */ r = amdgpu_gem_add_input_fence(filp, args->input_fence_syncobj_handles, args->num_syncobj_handles); @@ -891,6 +902,7 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data, goto error; } + /* Resolve the BO-VA mapping for this VM/BO combination. */ if (abo) { bo_va = amdgpu_vm_bo_find(&fpriv->vm, abo); if (!bo_va) { @@ -903,6 +915,11 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data, bo_va = NULL; } + /* + * Prepare the timeline syncobj node if the user requested a VM + * timeline update. This only allocates/looks up the syncobj and + * chain node; the actual fence is attached later. + */ r = amdgpu_gem_update_timeline_node(filp, args->vm_timeline_syncobj_out, args->vm_timeline_point, @@ -934,18 +951,30 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void *data, default: break; } + + /* + * Once the VA operation is done, update the VM and obtain the fence + * that represents the last relevant update for this mapping. This + * fence can then be exported to the user-visible VM timeline. + */ if (!r && !(args->flags & AMDGPU_VM_DELAY_UPDATE) && !adev->debug_vm) { fence = amdgpu_gem_va_update_vm(adev, &fpriv->vm, bo_va, args->operation); - if (timeline_syncobj) - amdgpu_gem_update_bo_mapping(filp, bo_va, - args->operation, - args->vm_timeline_point, - fence, timeline_syncobj, - timeline_chain); - else - dma_fence_put(fence); + if (timeline_syncobj && fence) { + if (!args->vm_timeline_point) { + /* Replace the existing fence when no point is given. */ + drm_syncobj_replace_fence(timeline_syncobj, + fence); + } else { + /* Attach the last-update fence at a specific point. */ + drm_syncobj_add_point(timeline_syncobj, + timeline_chain, + fence, + args->vm_timeline_point); + } + } + dma_fence_put(fence); } -- 2.51.0

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Linaro-mm-sig February 2026