On 2015년 03월 12일 13:36, Hyungwon Hwang wrote: > Checking whether the iommu mapping allocated is not enough to determine > whether iommu is supported properly or not. Even though there is mapping, > the kernel is going to be panicked without the iommu being allocated. > So this patch adds the additional condition to check whether iommu is > really supported or not. > > [ 0.960859] [drm] Initialized drm 1.1.0 20060810 > [ 1.016344] ------------[ cut here ]------------ > [ 1.016453] kernel BUG at drivers/iommu/exynos-iommu.c:481! > [ 1.020877] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM > [ 1.026693] Modules linked in: > [ 1.029736] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.0.0-rc1-00089-gb7abcc2-dirty #13 > [ 1.037802] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) > [ 1.043880] task: db0c0000 ti: db0a6000 task.ti: db0a6000 > [ 1.049268] PC is at __exynos_sysmmu_enable+0x188/0x214 > [ 1.054470] LR is at exynos_iommu_attach_device+0x44/0x118 > [ 1.059940] pc : [<c02bf0d0>] lr : [<c02bf1a0>] psr: 60000193 > [ 1.059940] sp : db0a7cd8 ip : 00000000 fp : 00000000 > [ 1.071394] r10: a0000113 r9 : 00000000 r8 : db355f90 > [ 1.076603] r7 : db25b210 r6 : db355640 r5 : 00000000 r4 : 00000000 > [ 1.083113] r3 : 00000000 r2 : db355640 r1 : 5b244000 r0 : db25b210 > [ 1.089624] Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel > [ 1.097001] Control: 10c5387d Table: 4000406a DAC: 00000015 > [ 1.102729] Process swapper/0 (pid: 1, stack limit = 0xdb0a6210) > [ 1.108719] Stack: (0xdb0a7cd8 to 0xdb0a8000) > [ 1.113060] 7cc0: 00000000 db355f80 > [ 1.121223] 7ce0: 00000000 db355640 db25b210 db355f90 00000000 a0000113 00000000 c02bf1a0 > [ 1.129383] 7d00: a0000113 c0115974 00200200 5b244000 db25b210 db25b210 da822c10 db157800 > [ 1.137542] 7d20: c0846540 00000000 c07ea3f4 c02bc8e8 db25b210 db278b40 da822c10 c001eb48 > [ 1.145701] 7d40: da822e10 db25b210 da822c10 c02ef444 da822e10 00000001 00000001 c02f0af4 > [ 1.153860] 7d60: da822e10 db2b0640 db2b25c0 db2b0640 00000000 c02f3850 db157800 00000000 > [ 1.162019] 7d80: db157800 00000000 00000000 db278900 00000000 c02eb7d8 db157800 00000000 > [ 1.170179] 7da0: 00000000 c08267b8 00000000 c02d4a44 c08e69f4 da822c00 db157800 c02d62c4 > [ 1.178337] 7dc0: 00000000 c07ea3f4 00000000 c02faf6c db2b07e0 db2b07e0 00000002 db2b0640 > [ 1.186497] 7de0: db2b07d0 c02f33f0 db2b0640 00000000 c0827130 c05a5230 da822c10 c02f34dc > [ 1.194656] 7e00: c08268c8 da822c10 00000001 c08268c8 c0826774 c02eb97c da822c10 da8c0cd0 > [ 1.202815] 7e20: 00000000 c08e6ab0 da822c10 c0826774 fffffdfb c02f9acc c08e6ab0 da822c10 > [ 1.210974] 7e40: c08466d8 00000000 c0826774 c02f7ea4 db2b8f80 c02491a0 db2b7a80 da822c10 > [ 1.219134] 7e60: c0826774 da822c44 c0827458 db2b7a80 0000007d c02f81cc 00000000 c0826774 > [ 1.227293] 7e80: c02f8140 c02f61b0 db11205c db2b93b4 c0826774 db2b8f80 00000000 c02f7540 > [ 1.235452] 7ea0: c070a3ac 00000000 c08e6a84 c0826774 00000000 c08e6a84 00000000 c02f8a48 > [ 1.243611] 7ec0: 00000000 00000000 c08e6a84 c02eb6f0 00000000 c070a3ac ffffffff 00000000 > [ 1.251770] 7ee0: 00000000 00000000 00000000 00000000 00000000 00000000 c08095a0 c08095a0 > [ 1.259930] 7f00: c02eb628 c0008a3c c0584ad4 c078395c 0000007d dfeff9b0 00000000 dfeff9af > [ 1.268089] 7f20: 00000000 db0a7f38 dfeffb46 dfeffb37 c0584ad4 c0040f40 0000395c 00000000 > [ 1.276248] 7f40: c0716918 dfeffb57 00000006 00000006 c080d618 dfeff980 c07fee24 00000006 > [ 1.284408] 7f60: c07ea3ec c0851c80 c0851c80 0000007d c07ea3f4 c07aee28 00000006 00000006 > [ 1.292566] 7f80: c07ae5ac c0047e88 00001c80 c055553c 00000000 00000000 00000000 00000000 > [ 1.300725] 7fa0: 00000000 c0555548 00000000 c000f390 00000000 00000000 00000000 00000000 > [ 1.308884] 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > [ 1.317044] 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000 ffffffff ffffffdf > [ 1.325220] [<c02bf0d0>] (__exynos_sysmmu_enable) from [<c02bf1a0>] (exynos_iommu_attach_device+0x44/0x118) > [ 1.334928] [<c02bf1a0>] (exynos_iommu_attach_device) from [<c02bc8e8>] (iommu_attach_device+0x1c/0xc8) > [ 1.344305] [<c02bc8e8>] (iommu_attach_device) from [<c001eb48>] (arm_iommu_attach_device+0x18/0x50) > [ 1.353420] [<c001eb48>] (arm_iommu_attach_device) from [<c02ef444>] (drm_iommu_attach_device+0x4c/0xcc) > [ 1.362880] [<c02ef444>] (drm_iommu_attach_device) from [<c02f0af4>] (fimd_bind+0x124/0x198) > [ 1.371298] [<c02f0af4>] (fimd_bind) from [<c02f3850>] (component_bind_all+0xc4/0x228) > [ 1.379195] [<c02f3850>] (component_bind_all) from [<c02eb7d8>] (exynos_drm_load+0xa0/0x148) > [ 1.387618] [<c02eb7d8>] (exynos_drm_load) from [<c02d4a44>] (drm_dev_register+0xa8/0x104) > [ 1.395864] [<c02d4a44>] (drm_dev_register) from [<c02d62c4>] (drm_platform_init+0x44/0xdc) > [ 1.404195] [<c02d62c4>] (drm_platform_init) from [<c02f33f0>] (try_to_bring_up_master.part.2+0xc8/0x108) > [ 1.413741] [<c02f33f0>] (try_to_bring_up_master.part.2) from [<c02f34dc>] (component_master_add_with_match+0xac/0x124) > [ 1.424505] [<c02f34dc>] (component_master_add_with_match) from [<c02eb97c>] (exynos_drm_platform_probe+0xfc/0x128) > [ 1.434925] [<c02eb97c>] (exynos_drm_platform_probe) from [<c02f9acc>] (platform_drv_probe+0x44/0xa4) > [ 1.444124] [<c02f9acc>] (platform_drv_probe) from [<c02f7ea4>] (driver_probe_device+0x13c/0x394) > [ 1.452977] [<c02f7ea4>] (driver_probe_device) from [<c02f81cc>] (__driver_attach+0x8c/0x90) > [ 1.461395] [<c02f81cc>] (__driver_attach) from [<c02f61b0>] (bus_for_each_dev+0x68/0x9c) > [ 1.469555] [<c02f61b0>] (bus_for_each_dev) from [<c02f7540>] (bus_add_driver+0x160/0x21c) > [ 1.477801] [<c02f7540>] (bus_add_driver) from [<c02f8a48>] (driver_register+0x78/0xf8) > [ 1.485786] [<c02f8a48>] (driver_register) from [<c02eb6f0>] (exynos_drm_init+0xc8/0x110) > [ 1.493946] [<c02eb6f0>] (exynos_drm_init) from [<c0008a3c>] (do_one_initcall+0xb8/0x1f0) > [ 1.502108] [<c0008a3c>] (do_one_initcall) from [<c07aee28>] (kernel_init_freeable+0x1d4/0x278) > [ 1.510787] [<c07aee28>] (kernel_init_freeable) from [<c0555548>] (kernel_init+0xc/0xe8) > [ 1.518859] [<c0555548>] (kernel_init) from [<c000f390>] (ret_from_fork+0x14/0x24) > [ 1.526406] Code: e3130004 1a00001e e3a06000 eaffffcf (e7f001f2) > [ 1.532505] ---[ end trace 03b1b443463b1342 ]--- > [ 1.537077] Kernel panic - not syncing: Fatal exception > > Signed-off-by: Hyungwon Hwang <human.hwang@xxxxxxxxxxx> > Cc: Inki Dae <inki.dae@xxxxxxxxxxx> > --- > drivers/gpu/drm/exynos/exynos_drm_iommu.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/exynos/exynos_drm_iommu.h b/drivers/gpu/drm/exynos/exynos_drm_iommu.h > index 35d2588..597bf70 100644 > --- a/drivers/gpu/drm/exynos/exynos_drm_iommu.h > +++ b/drivers/gpu/drm/exynos/exynos_drm_iommu.h > @@ -32,7 +32,7 @@ static inline bool is_drm_iommu_supported(struct drm_device *drm_dev) > #ifdef CONFIG_ARM_DMA_USE_IOMMU > struct device *dev = drm_dev->dev; > > - return dev->archdata.mapping ? true : false; > + return dev->archdata.mapping && dev->archdata.iommu; As of now, dev->archdata.iommu would always be NULL so above dev->archdata.iommu is same as false. Therefore, it has no any meaning. Even exynos iommu driver sets a iommu owner to dev->archdata.iommu, it seems not good for other driver accesses the iommu object directly. Thanks, Inki Dae > #else > return false; > #endif > -- > 1.9.1 > > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
