- Linux-stable-mirror - lists.linaro.org

[PATCH] KVM: x86/pmu: Do not accidentally create BTS events

by Fernand Sieber

From: Jan H. Schönherr <jschoenh(a)amazon.de> It is possible to degrade host performance by manipulating performance counters from a VM and tricking the host hypervisor to enable branch tracing. When the guest programs a CPU to track branch instructions and deliver an interrupt after exactly one branch instruction, the value one is handled by the host KVM/perf subsystems and treated incorrectly as a special value to enable the branch trace store (BTS) subsystem. It should not be possible to enable BTS from a guest. When BTS is enabled, it leads to general host performance degradation to both VMs and host. Perf considers the combination of PERF_COUNT_HW_BRANCH_INSTRUCTIONS with a sample_period of 1 a special case and handles this as a BTS event (see intel_pmu_has_bts_period()) -- a deviation from the usual semantic, where the sample_period represents the amount of branch instructions to encounter before the overflow handler is invoked. Nothing prevents a guest from programming its vPMU with the above settings (count branch, interrupt after one branch), which causes KVM to erroneously instruct perf to create a BTS event within pmc_reprogram_counter(), which does not have the desired semantics. The guest could also do more benign actions and request an interrupt after a more reasonable number of branch instructions via its vPMU. In that case counting works initially. However, KVM occasionally pauses and resumes the created performance counters. If the remaining amount of branch instructions until interrupt has reached 1 exactly, pmc_resume_counter() fails to resume the counter and a BTS event is created instead with its incorrect semantics. Fix this behavior by not passing the special value "1" as sample_period to perf. Instead, perform the same quirk that happens later in x86_perf_event_set_period() anyway, when the performance counter is transferred to the actual PMU: bump the sample_period to 2. Testing: From guest: `./wrmsr -p 12 0x186 0x1100c4` `./wrmsr -p 12 0xc1 0xffffffffffff` `./wrmsr -p 12 0x186 0x5100c4` This sequence sets up branch instruction counting, initializes the counter to overflow after one event (0xffffffffffff), and then enables edge detection (bit 18) for branch events. ./wrmsr -p 12 0x186 0x1100c4 Writes to IA32_PERFEVTSEL0 (0x186) Value 0x1100c4 breaks down as: Event = 0xC4 (Branch instructions) Bits 16-17: 0x1 (User mode only) Bit 22: 1 (Enable counter) ./wrmsr -p 12 0xc1 0xffffffffffff Writes to IA32_PMC0 (0xC1) Sets counter to maximum value (0xffffffffffff) This effectively sets up the counter to overflow on the next branch ./wrmsr -p 12 0x186 0x5100c4 Updates IA32_PERFEVTSEL0 again Similar to first command but adds bit 18 (0x4 to 0x5) Enables edge detection (bit 18) These MSR writes are trapped by the hypervisor in KVM and forwarded to the perf subsystem to create corresponding monitoring events. It is possible to repro this problem in a more realistic guest scenario: `perf record -e branches:u -c 2 -a &` `perf record -e branches:u -c 2 -a &` This presumably triggers the issue by KVM pausing and resuming the performance counter at the wrong moment, when its value is about to overflow. Signed-off-by: Jan H. Schönherr <jschoenh(a)amazon.de> Signed-off-by: Fernand Sieber <sieberf(a)amazon.com> Reviewed-by: David Woodhouse <dwmw(a)amazon.co.uk> Reviewed-by: Hendrik Borghorst <hborghor(a)amazon.de> Link: https://lore.kernel.org/r/20251124100220.238177-1-sieberf@amazon.com --- arch/x86/kvm/pmu.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c index 487ad19a236e..547512028e24 100644 --- a/arch/x86/kvm/pmu.c +++ b/arch/x86/kvm/pmu.c @@ -225,6 +225,19 @@ static u64 get_sample_period(struct kvm_pmc *pmc, u64 counter_value) { u64 sample_period = (-counter_value) & pmc_bitmask(pmc); + /* + * A sample_period of 1 might get mistaken by perf for a BTS event, see + * intel_pmu_has_bts_period(). This would prevent re-arming the counter + * via pmc_resume_counter(), followed by the accidental creation of an + * actual BTS event, which we do not want. + * + * Avoid this by bumping the sampling period. Note, that we do not lose + * any precision, because the same quirk happens later anyway (for + * different reasons) in x86_perf_event_set_period(). + */ + if (sample_period == 1) + sample_period = 2; + if (!sample_period) sample_period = pmc_bitmask(pmc) + 1; return sample_period; -- 2.43.0 Amazon Development Centre (South Africa) (Proprietary) Limited 29 Gogosoa Street, Observatory, Cape Town, Western Cape, 7925, South Africa Registration Number: 2004 / 034463 / 07

3 days, 3 hours

5
11
0 0

[PATCH v2] fjes: Add missing iounmap in fjes_hw_init()

by Haoxiang Li

In error paths, add fjes_hw_iounmap() to release the resource acquired by fjes_hw_iomap(). Add a goto label to do so. Fixes: 8cdc3f6c5d22 ("fjes: Hardware initialization routine") Cc: stable(a)vger.kernel.org Signed-off-by: Haoxiang Li <lihaoxiang(a)isrc.iscas.ac.cn> Signed-off-by: Simon Horman <horms(a)kernel.org> --- Changes in v2: - Use an idiomatic goto to do the error hanlding. - Thanks for pointing out the issues with the patch, Simon! --- drivers/net/fjes/fjes_hw.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/net/fjes/fjes_hw.c b/drivers/net/fjes/fjes_hw.c index b9b5554ea862..5ad2673f213d 100644 --- a/drivers/net/fjes/fjes_hw.c +++ b/drivers/net/fjes/fjes_hw.c @@ -334,7 +334,7 @@ int fjes_hw_init(struct fjes_hw *hw) ret = fjes_hw_reset(hw); if (ret) - return ret; + goto err_iounmap; fjes_hw_set_irqmask(hw, REG_ICTL_MASK_ALL, true); @@ -347,8 +347,10 @@ int fjes_hw_init(struct fjes_hw *hw) hw->max_epid = fjes_hw_get_max_epid(hw); hw->my_epid = fjes_hw_get_my_epid(hw); - if ((hw->max_epid == 0) || (hw->my_epid >= hw->max_epid)) - return -ENXIO; + if ((hw->max_epid == 0) || (hw->my_epid >= hw->max_epid)) { + ret = -ENXIO; + goto err_iounmap; + } ret = fjes_hw_setup(hw); @@ -356,6 +358,10 @@ int fjes_hw_init(struct fjes_hw *hw) hw->hw_info.trace_size = FJES_DEBUG_BUFFER_SIZE; return ret; + +err_iounmap: + fjes_hw_iounmap(hw); + return ret; } void fjes_hw_exit(struct fjes_hw *hw) -- 2.25.1

3 days, 4 hours

4
3
0 0

[PATCH v2] media: dvb-frontends: Fix out of bound for buffer

by Ilya Krutskih

Result of pointer shifting is out of bound for buffer 'prev_swp_freq' because of incrementation inside 'while' cycle in case more than 20 steps of it. Add check: prev_freq_num < 20 Cc: stable(a)vger.kernel.org # v5.10+ Fixes: 9a0bf528b4d6 ([media] move the dvb/frontends to drivers/media/dvb-frontends) Signed-off-by: Ilya Krutskih <devsec(a)tpz.ru> --- drivers/media/dvb-frontends/mb86a16.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/dvb-frontends/mb86a16.c b/drivers/media/dvb-frontends/mb86a16.c index 9033e39d75f4..da8985b91475 100644 --- a/drivers/media/dvb-frontends/mb86a16.c +++ b/drivers/media/dvb-frontends/mb86a16.c @@ -1188,7 +1188,7 @@ static int mb86a16_set_fe(struct mb86a16_state *state) signal_dupl = 0; for (j = 0; j < prev_freq_num; j++) { - if ((abs(prev_swp_freq[j] - swp_freq)) < (swp_ofs * 3 / 2)) { + if ((prev_freq_num < 20) && (abs(prev_swp_freq[j] - swp_freq)) < (swp_ofs * 3 / 2)) { signal_dupl = 1; dprintk(verbose, MB86A16_INFO, 1, "Probably Duplicate Signal, j = %d", j); } -- 2.43.0

3 days, 4 hours

1
0
0 0

[PATCH v3] zstd: fixed possible 'rtbTable' underflow in FSE_normalizeCount()

by Ilya Krutskih

'rtbTable' may be underflowed because 'proba' is used without checking for a non-negative as index of rtbTable[]. Add check: proba >= 0 Cc: stable(a)vger.kernel.org # v5.10+ Fixes: e0c1b49f5b67 ("lib: zstd: Upgrade to latest upstream zstd version 1.4.10") Signed-off-by: Ilya Krutskih <devsec(a)tpz.ru> --- lib/zstd/compress/fse_compress.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/lib/zstd/compress/fse_compress.c b/lib/zstd/compress/fse_compress.c index 44a3c10becf2..6b83f8bc943a 100644 --- a/lib/zstd/compress/fse_compress.c +++ b/lib/zstd/compress/fse_compress.c @@ -492,9 +492,10 @@ size_t FSE_normalizeCount (short* normalizedCounter, unsigned tableLog, stillToDistribute--; } else { short proba = (short)((count[s]*step) >> scale); - if (proba<8) { - U64 restToBeat = vStep * rtbTable[proba]; - proba += (count[s]*step) - ((U64)proba<<scale) > restToBeat; + if ((proba >= 0) && (proba < 8)) { + U64 restToBeat = vStep * rtbTable[proba]; + + proba += (count[s]*step) - ((U64)proba<<scale) > restToBeat; } if (proba > largestP) { largestP=proba; largest=s; } normalizedCounter[s] = proba; -- 2.43.0

3 days, 4 hours

1
0
0 0

[PATCH v4 01/22] drm/xe/svm: Fix a debug printout

by Thomas Hellström

Avoid spamming the log with drm_info(). Use drm_dbg() instead. Fixes: cc795e041034 ("drm/xe/svm: Make xe_svm_range_needs_migrate_to_vram() public") Cc: Matthew Brost <matthew.brost(a)intel.com> Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray(a)intel.com> Cc: <stable(a)vger.kernel.org> # v6.17+ Signed-off-by: Thomas Hellström <thomas.hellstrom(a)linux.intel.com> Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray(a)intel.com> --- drivers/gpu/drm/xe/xe_svm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c index 46977ec1e0de..36634c84d148 100644 --- a/drivers/gpu/drm/xe/xe_svm.c +++ b/drivers/gpu/drm/xe/xe_svm.c @@ -948,7 +948,7 @@ bool xe_svm_range_needs_migrate_to_vram(struct xe_svm_range *range, struct xe_vm xe_assert(vm->xe, IS_DGFX(vm->xe)); if (xe_svm_range_in_vram(range)) { - drm_info(&vm->xe->drm, "Range is already in VRAM\n"); + drm_dbg(&vm->xe->drm, "Range is already in VRAM\n"); return false; } -- 2.51.1

3 days, 5 hours

1
0
0 0

[PATCH v4] pmdomain: imx: Fix reference count leak in imx_gpc_probe()

by Wentao Liang

of_get_child_by_name() returns a node pointer with refcount incremented. Use the __free() attribute to manage the pgc_node reference, ensuring automatic of_node_put() cleanup when pgc_node goes out of scope. This eliminates the need for explicit error handling paths and avoids reference count leaks. Fixes: 721cabf6c660 ("soc: imx: move PGC handling to a new GPC driver") Cc: stable(a)vger.kernel.org Signed-off-by: Wentao Liang <vulab(a)iscas.ac.cn> --- Change in V4: - Fix typo error in code Change in V3: - Ensure variable is assigned when using cleanup attribute Change in V2: - Use __free() attribute instead of explicit of_node_put() calls --- drivers/pmdomain/imx/gpc.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/pmdomain/imx/gpc.c b/drivers/pmdomain/imx/gpc.c index f18c7e6e75dd..56a78cc86584 100644 --- a/drivers/pmdomain/imx/gpc.c +++ b/drivers/pmdomain/imx/gpc.c @@ -403,13 +403,12 @@ static int imx_gpc_old_dt_init(struct device *dev, struct regmap *regmap, static int imx_gpc_probe(struct platform_device *pdev) { const struct imx_gpc_dt_data *of_id_data = device_get_match_data(&pdev->dev); - struct device_node *pgc_node; + struct device_node *pgc_node __free(device_node) + = of_get_child_by_name(pdev->dev.of_node, "pgc"); struct regmap *regmap; void __iomem *base; int ret; - pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc"); - /* bail out if DT too old and doesn't provide the necessary info */ if (!of_property_present(pdev->dev.of_node, "#power-domain-cells") && !pgc_node) -- 2.34.1

3 days, 5 hours

2
1
0 0

[PATCH v3] drivers/pci: Decouple DPC from AER service

by Darshit Shah

According to PCIe r7.0, sec. 6.2.11, "Implementation Note: Determination of DPC Control", it is recommended that the Operating System link the enablement of Downstream Port Containment (DPC) to the enablement of Advanced Error Reporting (AER). However, AER is advertised only on Root Port (RP) or Root Complex Event Collector (RCEC) devices. On the other hand, DPC may be advertised on any PCIe device in the hierarchy. In fact, since the main usecase of DPC is for the switch upstream of an endpoint device to trigger a signal to the host-bridge, it is imperative that it be supported on non-RP, non-RCEC devices. Previously portdrv has interpreted the spec to mean that the AER service must be available on the same device in order for DPC to be available. This is not what the implementation note meant to imply. If the firmware hands Linux control of AER via _OSC on the host bridge upstream of the device, then Linux should be allowed to assume control of DPC on the device. The comment above this check alludes to this, by saying: > With dpc-native, allow Linux to use DPC even if it doesn't have > permission to use AER. However, permission to use AER is negotiated at the host bridge, not per-device. So we should not link DPC to enabling AER at the device. Instead, DPC should be enabled if the OS has control of AER for the host bridge that is upstream of the device in question, or if dpc-native was set on the command line. Cc: stable(a)vger.kernel.org Signed-off-by: Darshit Shah <darnshah(a)amazon.de> Reviewed-by: Lukas Wunner <lukas(a)wunner.de> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy(a)linux.intel.com> --- Changes from v2: * + stable(a)vger.kernel.org since moving to v6.2+ breaks DPC on our systems * Minor stylistic changes to commit message * NO functional changes drivers/pci/pcie/portdrv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/pcie/portdrv.c b/drivers/pci/pcie/portdrv.c index 38a41ccf79b9..8db2fa140ae2 100644 --- a/drivers/pci/pcie/portdrv.c +++ b/drivers/pci/pcie/portdrv.c @@ -264,7 +264,7 @@ static int get_port_device_capability(struct pci_dev *dev) */ if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_DPC) && pci_aer_available() && - (pcie_ports_dpc_native || (services & PCIE_PORT_SERVICE_AER))) + (host->native_aer || pcie_ports_dpc_native)) services |= PCIE_PORT_SERVICE_DPC; /* Enable bandwidth control if more than one speed is supported. */ -- 2.47.3 Amazon Web Services Development Center Germany GmbH Tamara-Danz-Str. 13 10243 Berlin Geschaeftsfuehrung: Christof Hellmis, Andreas Stieger Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B Sitz: Berlin Ust-ID: DE 365 538 597

3 days, 5 hours

1
0
0 0

[PATCH sched_ext/for-6.19-fixes] sched_ext: Fix bypass depth leak on scx_enable() failure

by Tejun Heo

scx_enable() calls scx_bypass(true) to initialize in bypass mode and then scx_bypass(false) on success to exit. If scx_enable() fails during task initialization - e.g. scx_cgroup_init() or scx_init_task() returns an error - it jumps to err_disable while bypass is still active. scx_disable_workfn() then calls scx_bypass(true/false) for its own bypass, leaving the bypass depth at 1 instead of 0. This causes the system to remain permanently in bypass mode after a failed scx_enable(). Failures after task initialization is complete - e.g. scx_tryset_enable_state() at the end - already call scx_bypass(false) before reaching the error path and are not affected. This only affects a subset of failure modes. Fix it by tracking whether scx_enable() called scx_bypass(true) in a bool and having scx_disable_workfn() call an extra scx_bypass(false) to clear it. This is a temporary measure as the bypass depth will be moved into the sched instance, which will make this tracking unnecessary. Fixes: 8c2090c504e9 ("sched_ext: Initialize in bypass mode") Cc: stable(a)vger.kernel.org # v6.12+ Reported-by: Chris Mason <clm(a)meta.com> Signed-off-by: Tejun Heo <tj(a)kernel.org> --- kernel/sched/ext.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -41,6 +41,13 @@ static bool scx_init_task_enabled; static bool scx_switching_all; DEFINE_STATIC_KEY_FALSE(__scx_switched_all); +/* + * Tracks whether scx_enable() called scx_bypass(true). Used to balance bypass + * depth on enable failure. Will be removed when bypass depth is moved into the + * sched instance. + */ +static bool scx_bypassed_for_enable; + static atomic_long_t scx_nr_rejected = ATOMIC_LONG_INIT(0); static atomic_long_t scx_hotplug_seq = ATOMIC_LONG_INIT(0); @@ -4318,6 +4325,11 @@ static void scx_disable_workfn(struct kt scx_dsp_max_batch = 0; free_kick_syncs(); + if (scx_bypassed_for_enable) { + scx_bypassed_for_enable = false; + scx_bypass(false); + } + mutex_unlock(&scx_enable_mutex); WARN_ON_ONCE(scx_set_enable_state(SCX_DISABLED) != SCX_DISABLING); @@ -4970,6 +4982,7 @@ static int scx_enable(struct sched_ext_o * Init in bypass mode to guarantee forward progress. */ scx_bypass(true); + scx_bypassed_for_enable = true; for (i = SCX_OPI_NORMAL_BEGIN; i < SCX_OPI_NORMAL_END; i++) if (((void (**)(void))ops)[i]) @@ -5067,6 +5080,7 @@ static int scx_enable(struct sched_ext_o scx_task_iter_stop(&sti); percpu_up_write(&scx_fork_rwsem); + scx_bypassed_for_enable = false; scx_bypass(false); if (!scx_tryset_enable_state(SCX_ENABLED, SCX_ENABLING)) { -- tejun

3 days, 5 hours

4
4
0 0

[PATCH] drm/gma500: Fix refcount leak in oaktrail_hdmi_setup

by Miaoqian Lin

pci_get_device() increments the reference count on the PCI device. Add missing pci_dev_put() in error paths to fix refcount leak. Found via static analysis and code review. Fixes: 1b082ccf5901 ("gma500: Add Oaktrail support") Cc: stable(a)vger.kernel.org Signed-off-by: Miaoqian Lin <linmq006(a)gmail.com> --- drivers/gpu/drm/gma500/oaktrail_hdmi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/gma500/oaktrail_hdmi.c b/drivers/gpu/drm/gma500/oaktrail_hdmi.c index 20d027d552c7..2be12acc93d2 100644 --- a/drivers/gpu/drm/gma500/oaktrail_hdmi.c +++ b/drivers/gpu/drm/gma500/oaktrail_hdmi.c @@ -712,10 +712,10 @@ void oaktrail_hdmi_setup(struct drm_device *dev) dev_info(dev->dev, "HDMI hardware present.\n"); return; - free: kfree(hdmi_dev); out: + pci_dev_put(pdev); return; } -- 2.25.1

3 days, 6 hours

1
0
0 0

[PATCH v3] drm/i915/gem: Zero-initialize the eb.vma array in i915_gem_do_execbuffer()

by Krzysztof Niemiec

Initialize the eb.vma array with values of 0 when the eb structure is first set up. In particular, this sets the eb->vma[i].vma pointers to NULL, simplifying cleanup and getting rid of the bug described below. During the execution of eb_lookup_vmas(), the eb->vma array is successively filled up with struct eb_vma objects. This process includes calling eb_add_vma(), which might fail; however, even in the event of failure, eb->vma[i].vma is set for the currently processed buffer. If eb_add_vma() fails, eb_lookup_vmas() returns with an error, which prompts a call to eb_release_vmas() to clean up the mess. Since eb_lookup_vmas() might fail during processing any (possibly not first) buffer, eb_release_vmas() checks whether a buffer's vma is NULL to know at what point did the lookup function fail. In eb_lookup_vmas(), eb->vma[i].vma is set to NULL if either the helper function eb_lookup_vma() or eb_validate_vma() fails. eb->vma[i+1].vma is set to NULL in case i915_gem_object_userptr_submit_init() fails; the current one needs to be cleaned up by eb_release_vmas() at this point, so the next one is set. If eb_add_vma() fails, neither the current nor the next vma is nullified, which is a source of a NULL deref bug described in the issue linked in the Closes tag. When entering eb_lookup_vmas(), the vma pointers are set to the slab poison value, instead of NULL. This doesn't matter for the actual lookup, since it gets overwritten anyway, however the eb_release_vmas() function only recognizes NULL as the stopping value, hence the pointers are being nullified as they go in case of intermediate failure. This patch changes the approach to filling them all with NULL at the start instead, rather than handling that manually during failure. Reported-by: Gangmin Kim <km.kim1503(a)gmail.com> Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15062 Fixes: 544460c33821 ("drm/i915: Multi-BB execbuf") Cc: <stable(a)vger.kernel.org> # 5.16.x Signed-off-by: Krzysztof Niemiec <krzysztof.niemiec(a)intel.com> --- I messed up the continuity in previous revisions; the original patch was sent as [1], and the first revision (which I didn't mark as v2 due to the title change) was sent as [2]. This is the full current changelog: v3: - use memset() to fill the entire eb.vma array with zeros instead of looping through the elements (Janusz) - add a comment clarifying the mechanism of the initial allocation (Janusz) - change the commit log again, including title - rearrange the tags to keep checkpatch happy v2: - set the eb->vma[i].vma pointers to NULL during setup instead of ad-hoc at failure (Janusz) - romanize the reporter's name (Andi, offline) - change the commit log, including title [1] https://patchwork.freedesktop.org/series/156832/ [2] https://patchwork.freedesktop.org/series/158036/ .../gpu/drm/i915/gem/i915_gem_execbuffer.c | 36 +++++++++---------- 1 file changed, 16 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c index b057c2fa03a4..5f2b736b53ab 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c @@ -951,13 +951,13 @@ static int eb_lookup_vmas(struct i915_execbuffer *eb) vma = eb_lookup_vma(eb, eb->exec[i].handle); if (IS_ERR(vma)) { err = PTR_ERR(vma); - goto err; + return err; } err = eb_validate_vma(eb, &eb->exec[i], vma); if (unlikely(err)) { i915_vma_put(vma); - goto err; + return err; } err = eb_add_vma(eb, &current_batch, i, vma); @@ -966,19 +966,8 @@ static int eb_lookup_vmas(struct i915_execbuffer *eb) if (i915_gem_object_is_userptr(vma->obj)) { err = i915_gem_object_userptr_submit_init(vma->obj); - if (err) { - if (i + 1 < eb->buffer_count) { - /* - * Execbuffer code expects last vma entry to be NULL, - * since we already initialized this entry, - * set the next value to NULL or we mess up - * cleanup handling. - */ - eb->vma[i + 1].vma = NULL; - } - + if (err) return err; - } eb->vma[i].flags |= __EXEC_OBJECT_USERPTR_INIT; eb->args->flags |= __EXEC_USERPTR_USED; @@ -986,10 +975,6 @@ static int eb_lookup_vmas(struct i915_execbuffer *eb) } return 0; - -err: - eb->vma[i].vma = NULL; - return err; } static int eb_lock_vmas(struct i915_execbuffer *eb) @@ -3375,7 +3360,9 @@ i915_gem_do_execbuffer(struct drm_device *dev, eb.exec = exec; eb.vma = (struct eb_vma *)(exec + args->buffer_count + 1); - eb.vma[0].vma = NULL; + + memset(eb.vma, 0x00, args->buffer_count * sizeof(struct eb_vma)); + eb.batch_pool = NULL; eb.invalid_flags = __EXEC_OBJECT_UNKNOWN_FLAGS; @@ -3584,7 +3571,16 @@ i915_gem_execbuffer2_ioctl(struct drm_device *dev, void *data, if (err) return err; - /* Allocate extra slots for use by the command parser */ + /* + * Allocate extra slots for use by the command parser. + * + * Note that this allocation handles two different arrays (the + * exec2_list array, and the eventual eb.vma array introduced in + * i915_gem_do_execubuffer()), that reside in virtually contiguous + * memory. Also note that the allocation doesn't fill the area with + * zeros (the first part doesn't need to be), but the second part only + * is explicitly zeroed later in i915_gem_do_execbuffer(). + */ exec2_list = kvmalloc_array(count + 2, eb_element_size(), __GFP_NOWARN | GFP_KERNEL); if (exec2_list == NULL) { -- 2.45.2

3 days, 7 hours

3
3
0 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-stable-mirror