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@samsung.com Cc: Inki Dae inki.dae@samsung.com
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