| Message ID | 20200101033949.755-1-masneyb@onstation.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | iommu/qcom: fix NULL pointer dereference during probe deferral | expand |
On Tue, Dec 31, 2019 at 10:39:49PM -0500, Brian Masney wrote: > When attempting to load the qcom-iommu driver, and an -EPROBE_DEFER > error occurs, the following attempted NULL pointer deference occurs: > > Unable to handle kernel NULL pointer dereference at virtual address 00000014 > pgd = (ptrval) > [00000014] *pgd=00000000 > Internal error: Oops: 5 [#1] PREEMPT SMP ARM > Modules linked in: > CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.5.0-rc2-next-20191220-00008-g7e71398bac41-dirty #67 > Hardware name: Generic DT based system > PC is at qcom_iommu_domain_free (./include/linux/pm_runtime.h:226 > linux/drivers/iommu/qcom_iommu.c:358) > LR is at release_iommu_mapping (arch/arm/mm/dma-mapping.c:2141) > pc : lr : psr: 60000013 > sp : ee89dc48 ip : 00000000 fp : c13a6684 > r10: c13a661c r9 : 00000000 r8 : c13a1240 > r7 : fffffdfb r6 : 00000000 r5 : edc32c80 r4 : edc32c9c > r3 : 00000000 r2 : 00000001 r1 : 00000004 r0 : edc32c9c > Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none > Control: 10c5787d Table: 0020406a DAC: 00000051 > Process swapper/0 (pid: 1, stack limit = 0x(ptrval)) > Stack: (0xee89dc48 to 0xee89e000) > dc40: edc3cc10 edc31ba0 00000000 c0316af8 edc3cc10 edc31b80 > dc60: 00000000 c0319684 c14341ac edc3cc10 00000000 c083bd88 edc3cc10 c13a1240 > dc80: c083c2e8 c13a6684 c13a661c c13a6508 c13a661c c083c134 c13a1240 ee89dcec > dca0: edc3cc10 00000000 ee89dcec c083c2e8 c13a6684 c13a661c c13a6508 c13a661c > dcc0: c13a6684 c083a31c c13a6684 ee82a86c edc32538 c1304e48 edc3cc10 00000001 > dce0: edc3cc54 c083bc08 ee82a880 edc3cc10 00000001 c1304e48 edc3cc10 edc3cc10 > dd00: c13a69e8 c083b010 edc3cc10 00000000 eea1fc10 c0837aac 00000200 00000000 > dd20: 00000000 00000000 00000000 c1304e48 00000000 edc3cc00 eea1fc10 00000000 > dd40: 00000000 eeff42f4 00000000 00000001 00000000 c09e96e0 eeff42a4 00000000 > dd60: 00000000 00000000 eea1fc10 c09e98bc 00000001 eea1fc10 00000000 eea1fc10 > dd80: edc32980 c1391580 eea1fc10 00000001 eea1fc10 c0850f90 c2706d80 c14368c0 > dda0: 60000013 c1304e48 00000106 eeff42a4 eeff3fa0 00000000 00000000 eea1fc10 > ddc0: 00000001 c1248900 00000106 c09e9bd0 00000001 c0c2ee64 eea1fc00 eea1fc10 > dde0: eea1fc10 00000000 c13a5b70 00000000 c1248900 c081496c c1023d84 00000000 > de00: eeff3fa0 c2706ddc c2706ddc c1304e48 00000001 00000000 eea1fc10 c13a5b70 > de20: 00000000 c13a5b70 00000000 c1248900 00000106 c083dfb8 c14341ac eea1fc10 > de40: 00000000 c083be58 eea1fc10 c13a5b70 c13a5b70 c13a69e8 c12003ec c123a854 > de60: c1248900 c083c134 c1248900 c09e6f3c c0d8d514 eea1fc10 00000000 c13a5b70 > de80: c13a69e8 c12003ec c123a854 c1248900 00000106 c083c3e0 00000000 c13a5b70 > dea0: eea1fc10 c083c440 00000000 c13a5b70 c083c3e8 c083a23c 00000106 ee82a858 > dec0: eea052b4 c1304e48 c13a5b70 edc32900 00000000 c083b270 c1043084 c121d1d8 > dee0: ffffe000 c13a5b70 c121d1d8 ffffe000 00000000 c083cfcc c13ece60 c121d1d8 > df00: ffffe000 c0302f90 00000106 c034407c 00000000 c10e3a00 c1044dd0 c12003ec > df20: 00000000 00000006 00000006 c0fbecac c0fada88 c0fada3c 00000000 efffcbf8 > df40: efffcc0d c1304e48 00000000 00000006 c13f9500 c1304e48 c123a830 00000007 > df60: c13f9500 c13f9500 c123a834 c1200f64 00000006 00000006 00000000 c12003ec > df80: c0c28194 00000000 c0c28194 00000000 00000000 00000000 00000000 00000000 > dfa0: 00000000 c0c2819c 00000000 c03010e8 00000000 00000000 00000000 00000000 > dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 > (qcom_iommu_domain_free) from release_iommu_mapping (arch/arm/mm/dma-mapping.c:2141) > (release_iommu_mapping) from arch_teardown_dma_ops (./include/linux/dma-mapping.h:271 > linux/arch/arm/mm/dma-mapping.c:2335) > (arch_teardown_dma_ops) from really_probe (drivers/base/dd.c:607) > (really_probe) from driver_probe_device (drivers/base/dd.c:721) > (driver_probe_device) from bus_for_each_drv (drivers/base/bus.c:431) > (bus_for_each_drv) from __device_attach (drivers/base/dd.c:896) > (__device_attach) from bus_probe_device (drivers/base/bus.c:491) > (bus_probe_device) from device_add (drivers/base/core.c:2488) > (device_add) from of_platform_device_create_pdata (drivers/of/platform.c:189) > (of_platform_device_create_pdata) from of_platform_bus_create > (drivers/of/platform.c:393 linux/drivers/of/platform.c:346) > (of_platform_bus_create) from of_platform_populate (drivers/of/platform.c:486) > (of_platform_populate) from msm_pdev_probe (drivers/gpu/drm/msm/msm_drv.c:1197 > linux/drivers/gpu/drm/msm/msm_drv.c:1281) > (msm_pdev_probe) from platform_drv_probe (drivers/base/platform.c:726) > (platform_drv_probe) from really_probe (drivers/base/dd.c:553) > (really_probe) from driver_probe_device (drivers/base/dd.c:721) > (driver_probe_device) from device_driver_attach (drivers/base/dd.c:995) > (device_driver_attach) from __driver_attach (drivers/base/dd.c:1074) > (__driver_attach) from bus_for_each_dev (drivers/base/bus.c:304) > (bus_for_each_dev) from bus_add_driver (drivers/base/bus.c:623) > (bus_add_driver) from driver_register (drivers/base/driver.c:172) > (driver_register) from do_one_initcall (./include/linux/compiler.h:232 > linux/./include/linux/jump_label.h:254 > linux/./include/linux/jump_label.h:264 > linux/./include/trace/events/initcall.h:48 linux/init/main.c:941) > (do_one_initcall) from kernel_init_freeable (init/main.c:1013 > linux/init/main.c:1022 linux/init/main.c:1039 > linux/init/main.c:1231) > (kernel_init_freeable) from kernel_init (init/main.c:1127) > (kernel_init) from ret_from_fork (arch/arm/kernel/entry-common.S:156) > Exception stack(0xee89dfb0 to 0xee89dff8) > dfa0: 00000000 00000000 00000000 00000000 > dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 > Code: e92d4070 e1a04000 e3a01004 e240501c (e5930014) > All code > ======== > 0: 70 40 jo 0x42 > 2: 2d e9 00 40 a0 sub $0xa04000e9,%eax > 7: e1 04 loope 0xd > 9: 10 a0 e3 1c 50 40 adc %ah,0x40501ce3(%rax) > f: e2 14 loop 0x25 > 11:* 00 .byte 0x0 <-- trapping instruction > 12: 93 xchg %eax,%ebx > 13: e5 .byte 0xe5 > > Code starting with the faulting instruction > =========================================== > 0: 14 00 adc $0x0,%al > 2: 93 xchg %eax,%ebx > 3: e5 .byte 0xe5 > > qcom_iommu_domain_free() has a WARN_ON() that checks to see if the value > of iommu is NULL and returns early, so iommu->dev will always be NULL. > qcom_iommu_detach_dev() is called prior to freeing the IOMMU domain and > is what sets the iommu member to NULL. > > Let's fix this by adding the 'struct dev' pointer to the > qcom_iommu_domain struct. > > Signed-off-by: Brian Masney <masneyb@onstation.org> > Fixes: 0ae349a0f33fb ("iommu/qcom: Add qcom_iommu") Thanks for the patch! This problem has been annoying me for quite a while. Recently I was debugging some IOMMU issues and this crash literally happened whenever there was something wrong during IOMMU initialization. :) I was not quite sure how to fix it, but this patch seems to work fine. FWIW: Tested-by: Stephan Gerhold <stephan@gerhold.net> > --- > drivers/iommu/qcom_iommu.c | 12 ++++++++++-- > 1 file changed, 10 insertions(+), 2 deletions(-) > > diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c > index 52f38292df5b..ac4354773c06 100644 > --- a/drivers/iommu/qcom_iommu.c > +++ b/drivers/iommu/qcom_iommu.c > @@ -65,6 +65,7 @@ struct qcom_iommu_domain { > struct mutex init_mutex; /* Protects iommu pointer */ > struct iommu_domain domain; > struct qcom_iommu_dev *iommu; > + struct device *dev; > }; > > static struct qcom_iommu_domain *to_qcom_iommu_domain(struct iommu_domain *dom) > @@ -243,6 +244,13 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain, > }; > > qcom_domain->iommu = qcom_iommu; > + > + /* > + * This dev pointer is needed to avoid a NULL pointer dereference in > + * qcom_iommu_domain_free(). > + */ > + qcom_domain->dev = qcom_iommu->dev; > + > pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, fwspec); > if (!pgtbl_ops) { > dev_err(qcom_iommu->dev, "failed to allocate pagetable ops\n"); > @@ -355,11 +363,11 @@ static void qcom_iommu_domain_free(struct iommu_domain *domain) > * cannot rely on the device_link. Make sure the IOMMU is on to > * avoid unclocked accesses in the TLB inv path: > */ > - pm_runtime_get_sync(qcom_domain->iommu->dev); > + pm_runtime_get_sync(qcom_domain->dev); > > free_io_pgtable_ops(qcom_domain->pgtbl_ops); > > - pm_runtime_put_sync(qcom_domain->iommu->dev); > + pm_runtime_put_sync(qcom_domain->dev); > > kfree(qcom_domain); > } > -- > 2.21.0 >
On Tue, Dec 31, 2019 at 10:39:49PM -0500, Brian Masney wrote: [...] > (kernel_init) from ret_from_fork (arch/arm/kernel/entry-common.S:156) > Exception stack(0xee89dfb0 to 0xee89dff8) > dfa0: 00000000 00000000 00000000 00000000 > dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 > Code: e92d4070 e1a04000 e3a01004 e240501c (e5930014) This looks like ARM code... > All code > ======== > 0: 70 40 jo 0x42 > 2: 2d e9 00 40 a0 sub $0xa04000e9,%eax > 7: e1 04 loope 0xd > 9: 10 a0 e3 1c 50 40 adc %ah,0x40501ce3(%rax) > f: e2 14 loop 0x25 > 11:* 00 .byte 0x0 <-- trapping instruction > 12: 93 xchg %eax,%ebx > 13: e5 .byte 0xe5 ... disassembled as x86 code. I suspect that scripts/decodecode picked up the wrong architecture somehow. Perhaps CROSS_COMPILE wasn't set? > > Code starting with the faulting instruction > =========================================== > 0: 14 00 adc $0x0,%al > 2: 93 xchg %eax,%ebx > 3: e5 .byte 0xe5 Greetings and a happy new year, Jonathan Neuschäfer
On Tue, Dec 31, 2019 at 10:39:49PM -0500, Brian Masney wrote: > drivers/iommu/qcom_iommu.c | 12 ++++++++++-- > 1 file changed, 10 insertions(+), 2 deletions(-) Shortened commit-message a bit and applied for v5.5, thanks.
On Tue, Jan 07, 2020 at 02:25:30PM +0100, Joerg Roedel wrote: > On Tue, Dec 31, 2019 at 10:39:49PM -0500, Brian Masney wrote: > > drivers/iommu/qcom_iommu.c | 12 ++++++++++-- > > 1 file changed, 10 insertions(+), 2 deletions(-) > > Shortened commit-message a bit and applied for v5.5, thanks. You might want to hold off on applying this since it looks like Robin Murphy has a better fix. https://lore.kernel.org/lkml/fc055443-8716-4a0e-b4d5-311517d71ea0@arm.com/ Brian
On Tue, Jan 07, 2020 at 09:00:14AM -0500, Brian Masney wrote: > On Tue, Jan 07, 2020 at 02:25:30PM +0100, Joerg Roedel wrote: > > On Tue, Dec 31, 2019 at 10:39:49PM -0500, Brian Masney wrote: > > > drivers/iommu/qcom_iommu.c | 12 ++++++++++-- > > > 1 file changed, 10 insertions(+), 2 deletions(-) > > > > Shortened commit-message a bit and applied for v5.5, thanks. > > You might want to hold off on applying this since it looks like Robin > Murphy has a better fix. > > https://lore.kernel.org/lkml/fc055443-8716-4a0e-b4d5-311517d71ea0@arm.com/ Alright, thanks for the heads-up. I dropped that patch from my fixes branch. Regards, Joerg
diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c index 52f38292df5b..ac4354773c06 100644 --- a/drivers/iommu/qcom_iommu.c +++ b/drivers/iommu/qcom_iommu.c @@ -65,6 +65,7 @@ struct qcom_iommu_domain { struct mutex init_mutex; /* Protects iommu pointer */ struct iommu_domain domain; struct qcom_iommu_dev *iommu; + struct device *dev; }; static struct qcom_iommu_domain *to_qcom_iommu_domain(struct iommu_domain *dom) @@ -243,6 +244,13 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain, }; qcom_domain->iommu = qcom_iommu; + + /* + * This dev pointer is needed to avoid a NULL pointer dereference in + * qcom_iommu_domain_free(). + */ + qcom_domain->dev = qcom_iommu->dev; + pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, fwspec); if (!pgtbl_ops) { dev_err(qcom_iommu->dev, "failed to allocate pagetable ops\n"); @@ -355,11 +363,11 @@ static void qcom_iommu_domain_free(struct iommu_domain *domain) * cannot rely on the device_link. Make sure the IOMMU is on to * avoid unclocked accesses in the TLB inv path: */ - pm_runtime_get_sync(qcom_domain->iommu->dev); + pm_runtime_get_sync(qcom_domain->dev); free_io_pgtable_ops(qcom_domain->pgtbl_ops); - pm_runtime_put_sync(qcom_domain->iommu->dev); + pm_runtime_put_sync(qcom_domain->dev); kfree(qcom_domain); }
When attempting to load the qcom-iommu driver, and an -EPROBE_DEFER error occurs, the following attempted NULL pointer deference occurs: Unable to handle kernel NULL pointer dereference at virtual address 00000014 pgd = (ptrval) [00000014] *pgd=00000000 Internal error: Oops: 5 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.5.0-rc2-next-20191220-00008-g7e71398bac41-dirty #67 Hardware name: Generic DT based system PC is at qcom_iommu_domain_free (./include/linux/pm_runtime.h:226 linux/drivers/iommu/qcom_iommu.c:358) LR is at release_iommu_mapping (arch/arm/mm/dma-mapping.c:2141) pc : lr : psr: 60000013 sp : ee89dc48 ip : 00000000 fp : c13a6684 r10: c13a661c r9 : 00000000 r8 : c13a1240 r7 : fffffdfb r6 : 00000000 r5 : edc32c80 r4 : edc32c9c r3 : 00000000 r2 : 00000001 r1 : 00000004 r0 : edc32c9c Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5787d Table: 0020406a DAC: 00000051 Process swapper/0 (pid: 1, stack limit = 0x(ptrval)) Stack: (0xee89dc48 to 0xee89e000) dc40: edc3cc10 edc31ba0 00000000 c0316af8 edc3cc10 edc31b80 dc60: 00000000 c0319684 c14341ac edc3cc10 00000000 c083bd88 edc3cc10 c13a1240 dc80: c083c2e8 c13a6684 c13a661c c13a6508 c13a661c c083c134 c13a1240 ee89dcec dca0: edc3cc10 00000000 ee89dcec c083c2e8 c13a6684 c13a661c c13a6508 c13a661c dcc0: c13a6684 c083a31c c13a6684 ee82a86c edc32538 c1304e48 edc3cc10 00000001 dce0: edc3cc54 c083bc08 ee82a880 edc3cc10 00000001 c1304e48 edc3cc10 edc3cc10 dd00: c13a69e8 c083b010 edc3cc10 00000000 eea1fc10 c0837aac 00000200 00000000 dd20: 00000000 00000000 00000000 c1304e48 00000000 edc3cc00 eea1fc10 00000000 dd40: 00000000 eeff42f4 00000000 00000001 00000000 c09e96e0 eeff42a4 00000000 dd60: 00000000 00000000 eea1fc10 c09e98bc 00000001 eea1fc10 00000000 eea1fc10 dd80: edc32980 c1391580 eea1fc10 00000001 eea1fc10 c0850f90 c2706d80 c14368c0 dda0: 60000013 c1304e48 00000106 eeff42a4 eeff3fa0 00000000 00000000 eea1fc10 ddc0: 00000001 c1248900 00000106 c09e9bd0 00000001 c0c2ee64 eea1fc00 eea1fc10 dde0: eea1fc10 00000000 c13a5b70 00000000 c1248900 c081496c c1023d84 00000000 de00: eeff3fa0 c2706ddc c2706ddc c1304e48 00000001 00000000 eea1fc10 c13a5b70 de20: 00000000 c13a5b70 00000000 c1248900 00000106 c083dfb8 c14341ac eea1fc10 de40: 00000000 c083be58 eea1fc10 c13a5b70 c13a5b70 c13a69e8 c12003ec c123a854 de60: c1248900 c083c134 c1248900 c09e6f3c c0d8d514 eea1fc10 00000000 c13a5b70 de80: c13a69e8 c12003ec c123a854 c1248900 00000106 c083c3e0 00000000 c13a5b70 dea0: eea1fc10 c083c440 00000000 c13a5b70 c083c3e8 c083a23c 00000106 ee82a858 dec0: eea052b4 c1304e48 c13a5b70 edc32900 00000000 c083b270 c1043084 c121d1d8 dee0: ffffe000 c13a5b70 c121d1d8 ffffe000 00000000 c083cfcc c13ece60 c121d1d8 df00: ffffe000 c0302f90 00000106 c034407c 00000000 c10e3a00 c1044dd0 c12003ec df20: 00000000 00000006 00000006 c0fbecac c0fada88 c0fada3c 00000000 efffcbf8 df40: efffcc0d c1304e48 00000000 00000006 c13f9500 c1304e48 c123a830 00000007 df60: c13f9500 c13f9500 c123a834 c1200f64 00000006 00000006 00000000 c12003ec df80: c0c28194 00000000 c0c28194 00000000 00000000 00000000 00000000 00000000 dfa0: 00000000 c0c2819c 00000000 c03010e8 00000000 00000000 00000000 00000000 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 (qcom_iommu_domain_free) from release_iommu_mapping (arch/arm/mm/dma-mapping.c:2141) (release_iommu_mapping) from arch_teardown_dma_ops (./include/linux/dma-mapping.h:271 linux/arch/arm/mm/dma-mapping.c:2335) (arch_teardown_dma_ops) from really_probe (drivers/base/dd.c:607) (really_probe) from driver_probe_device (drivers/base/dd.c:721) (driver_probe_device) from bus_for_each_drv (drivers/base/bus.c:431) (bus_for_each_drv) from __device_attach (drivers/base/dd.c:896) (__device_attach) from bus_probe_device (drivers/base/bus.c:491) (bus_probe_device) from device_add (drivers/base/core.c:2488) (device_add) from of_platform_device_create_pdata (drivers/of/platform.c:189) (of_platform_device_create_pdata) from of_platform_bus_create (drivers/of/platform.c:393 linux/drivers/of/platform.c:346) (of_platform_bus_create) from of_platform_populate (drivers/of/platform.c:486) (of_platform_populate) from msm_pdev_probe (drivers/gpu/drm/msm/msm_drv.c:1197 linux/drivers/gpu/drm/msm/msm_drv.c:1281) (msm_pdev_probe) from platform_drv_probe (drivers/base/platform.c:726) (platform_drv_probe) from really_probe (drivers/base/dd.c:553) (really_probe) from driver_probe_device (drivers/base/dd.c:721) (driver_probe_device) from device_driver_attach (drivers/base/dd.c:995) (device_driver_attach) from __driver_attach (drivers/base/dd.c:1074) (__driver_attach) from bus_for_each_dev (drivers/base/bus.c:304) (bus_for_each_dev) from bus_add_driver (drivers/base/bus.c:623) (bus_add_driver) from driver_register (drivers/base/driver.c:172) (driver_register) from do_one_initcall (./include/linux/compiler.h:232 linux/./include/linux/jump_label.h:254 linux/./include/linux/jump_label.h:264 linux/./include/trace/events/initcall.h:48 linux/init/main.c:941) (do_one_initcall) from kernel_init_freeable (init/main.c:1013 linux/init/main.c:1022 linux/init/main.c:1039 linux/init/main.c:1231) (kernel_init_freeable) from kernel_init (init/main.c:1127) (kernel_init) from ret_from_fork (arch/arm/kernel/entry-common.S:156) Exception stack(0xee89dfb0 to 0xee89dff8) dfa0: 00000000 00000000 00000000 00000000 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 Code: e92d4070 e1a04000 e3a01004 e240501c (e5930014) All code ======== 0: 70 40 jo 0x42 2: 2d e9 00 40 a0 sub $0xa04000e9,%eax 7: e1 04 loope 0xd 9: 10 a0 e3 1c 50 40 adc %ah,0x40501ce3(%rax) f: e2 14 loop 0x25 11:* 00 .byte 0x0 <-- trapping instruction 12: 93 xchg %eax,%ebx 13: e5 .byte 0xe5 Code starting with the faulting instruction =========================================== 0: 14 00 adc $0x0,%al 2: 93 xchg %eax,%ebx 3: e5 .byte 0xe5 qcom_iommu_domain_free() has a WARN_ON() that checks to see if the value of iommu is NULL and returns early, so iommu->dev will always be NULL. qcom_iommu_detach_dev() is called prior to freeing the IOMMU domain and is what sets the iommu member to NULL. Let's fix this by adding the 'struct dev' pointer to the qcom_iommu_domain struct. Signed-off-by: Brian Masney <masneyb@onstation.org> Fixes: 0ae349a0f33fb ("iommu/qcom: Add qcom_iommu") --- drivers/iommu/qcom_iommu.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)