FYI, we noticed the following commit:

https://github.com/0day-ci/linux Chris-Wilson/drm-i915-Fix-gen8-semaphores-id-for-legacy-mode/20160411-184850
commit 58fac268c7380fd0084a351f334e6e9b875cc74c ("drm/i915: Enable legacy/semaphores for CI")

on test machine: lkp-bdw01: 4 threads Broadwell ULT with 4G memory

caused below changes:


<5>[   22.604397] Key type id_resolver registered
<5>[   22.609172] Key type id_legacy registered
<4>[   24.326301] ------------[ cut here ]------------
<4>[   24.331586] WARNING: CPU: 1 PID: 593 at drivers/gpu/drm/i915/i915_gem_execbuffer.c:1253 i915_gem_ringbuffer_submission+0x17c/0x550 [i915]()
<4>[   24.347923] render ring didn't clear reload
<4>[   24.352686] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver btrfs xor raid6_pq sg snd_hda_codec_hdmi sd_mod x86_pkg_temp_thermal coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper ppdev cryptd i2c_hid i915 serio_raw ahci drm_kms_helper libahci pcspkr syscopyarea sysfillrect sysimgblt fb_sys_fops snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_pcm libata shpchp snd_timer snd soundcore drm sdhci_acpi video sdhci mmc_core dw_dmac dw_dmac_core i2c_designware_platform i2c_designware_core winbond_cir rc_core parport_pc parport spi_pxa2xx_platform acpi_pad
<4>[   24.420580] CPU: 1 PID: 593 Comm: kms_flip Not tainted 4.5.0-rc7-01697-g58fac26 #1
<4>[   24.429188] Hardware name: Intel Corporation Broadwell Client platform/WhiteTip Mountain 1, BIOS BDW-E1R1.86C.0120.R00.1504020241 04/02/2015
<4>[   24.443525]  0000000000000000 ffff88007af83ae0 ffffffff814261da ffff88007af83b28
<4>[   24.451970]  ffffffffa03c8d38 ffff88007af83b18 ffffffff81079fe6 ffff88007af83ce8
<4>[   24.460417]  ffff88007a3e9a80 0000000000000000 ffff88007a3e99d0 0000000000000001
<4>[   24.468864] Call Trace:
<4>[   24.471648]  [<ffffffff814261da>] dump_stack+0x63/0x89
<4>[   24.477484]  [<ffffffff81079fe6>] warn_slowpath_common+0x86/0xc0
<4>[   24.484315]  [<ffffffff8107a06c>] warn_slowpath_fmt+0x4c/0x50
<4>[   24.490866]  [<ffffffffa030fa6c>] i915_gem_ringbuffer_submission+0x17c/0x550 [i915]
<4>[   24.499595]  [<ffffffffa030f535>] i915_gem_do_execbuffer+0x12a5/0x12f0 [i915]
<4>[   24.508515]  [<ffffffffa031773f>] ? i915_gem_gtt_prepare_object+0x6f/0xa0 [i915]
<4>[   24.516934]  [<ffffffff8109e889>] ? __might_sleep+0x49/0x80
<4>[   24.523292]  [<ffffffffa02fd724>] ? intel_runtime_pm_put+0x64/0xc0 [i915]
<4>[   24.531025]  [<ffffffffa0310269>] i915_gem_execbuffer2+0xd9/0x2a0 [i915]
<4>[   24.538656]  [<ffffffffa0137a62>] drm_ioctl+0x142/0x590 [drm]
<4>[   24.545191]  [<ffffffff8116ecf0>] ? unlock_page+0x70/0x80
<4>[   24.551341]  [<ffffffffa0310190>] ? i915_gem_execbuffer+0x350/0x350 [i915]
<4>[   24.559161]  [<ffffffff813bee2b>] ? selinux_file_ioctl+0x11b/0x1f0
<4>[   24.566189]  [<ffffffff8120784f>] do_vfs_ioctl+0x8f/0x670
<4>[   24.572329]  [<ffffffff813b43a3>] ? security_file_ioctl+0x43/0x60
<4>[   24.579258]  [<ffffffff81207ea9>] SyS_ioctl+0x79/0x90
<4>[   24.585004]  [<ffffffff818e5bae>] entry_SYSCALL_64_fastpath+0x12/0x6d
<4>[   24.592342] ---[ end trace f380b5d7495721f6 ]---
<47>



To reproduce:

        git clone git://git.kernel.org/pub/scm/linux/kernel/git/wfg/lkp-tests.git
        cd lkp-tests
        bin/lkp install job.yaml  # job file is attached in this email
        bin/lkp run     job.yaml



Thanks,
Xiaolong Ye