Hi Julien,
On 29/04/2019 15:44, Julien Grall wrote:
> Hi all,
>
> On RT, the function iommu_dma_map_msi_msg expects to be called from preemptible
> context. However, this is not always the case resulting a splat with
> !CONFIG_DEBUG_ATOMIC_SLEEP:
>
> [ 48.875777] BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:974
> [ 48.875779] in_atomic(): 1, irqs_disabled(): 128, pid: 2103, name: ip
> [ 48.875782] INFO: lockdep is turned off.
> [ 48.875784] irq event stamp: 10684
> [ 48.875786] hardirqs last enabled at (10683): [<ffff0000110c8d70>] _raw_spin_unlock_irqrestore+0x88/0x90
> [ 48.875791] hardirqs last disabled at (10684): [<ffff0000110c8b2c>] _raw_spin_lock_irqsave+0x24/0x68
> [ 48.875796] softirqs last enabled at (0): [<ffff0000100ec590>] copy_process.isra.1.part.2+0x8d8/0x1970
> [ 48.875801] softirqs last disabled at (0): [<0000000000000000>] (null)
> [ 48.875805] Preemption disabled at:
> [ 48.875805] [<ffff000010189ae8>] __setup_irq+0xd8/0x6c0
> [ 48.875811] CPU: 2 PID: 2103 Comm: ip Not tainted 5.0.3-rt1-00007-g42ede9a0fed6 #45
> [ 48.875815] Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Jan 23 2017
> [ 48.875817] Call trace:
> [ 48.875818] dump_backtrace+0x0/0x140
> [ 48.875821] show_stack+0x14/0x20
> [ 48.875823] dump_stack+0xa0/0xd4
> [ 48.875827] ___might_sleep+0x16c/0x1f8
> [ 48.875831] rt_spin_lock+0x5c/0x70
> [ 48.875835] iommu_dma_map_msi_msg+0x5c/0x1d8
> [ 48.875839] gicv2m_compose_msi_msg+0x3c/0x48
> [ 48.875843] irq_chip_compose_msi_msg+0x40/0x58
> [ 48.875846] msi_domain_activate+0x38/0x98
> [ 48.875849] __irq_domain_activate_irq+0x58/0xa0
> [ 48.875852] irq_domain_activate_irq+0x34/0x58
> [ 48.875855] irq_activate+0x28/0x30
> [ 48.875858] __setup_irq+0x2b0/0x6c0
> [ 48.875861] request_threaded_irq+0xdc/0x188
> [ 48.875865] sky2_setup_irq+0x44/0xf8
> [ 48.875868] sky2_open+0x1a4/0x240
> [ 48.875871] __dev_open+0xd8/0x188
> [ 48.875874] __dev_change_flags+0x164/0x1f0
> [ 48.875877] dev_change_flags+0x20/0x60
> [ 48.875879] do_setlink+0x2a0/0xd30
> [ 48.875882] __rtnl_newlink+0x5b4/0x6d8
> [ 48.875885] rtnl_newlink+0x50/0x78
> [ 48.875888] rtnetlink_rcv_msg+0x178/0x640
> [ 48.875891] netlink_rcv_skb+0x58/0x118
> [ 48.875893] rtnetlink_rcv+0x14/0x20
> [ 48.875896] netlink_unicast+0x188/0x200
> [ 48.875898] netlink_sendmsg+0x248/0x3d8
> [ 48.875900] sock_sendmsg+0x18/0x40
> [ 48.875904] ___sys_sendmsg+0x294/0x2d0
> [ 48.875908] __sys_sendmsg+0x68/0xb8
> [ 48.875911] __arm64_sys_sendmsg+0x20/0x28
> [ 48.875914] el0_svc_common+0x90/0x118
> [ 48.875918] el0_svc_handler+0x2c/0x80
> [ 48.875922] el0_svc+0x8/0xc
>
> This series is a first attempt to rework how MSI are mapped and composed
> when an IOMMU is present.
>
> I was able to test the changes in GICv2m and GICv3 ITS. I don't have
> hardware for the other interrupt controllers.
>
> Cheers,
>
> Julien Grall (7):
> genirq/msi: Add a new field in msi_desc to store an IOMMU cookie
> iommu/dma-iommu: Split iommu_dma_map_msi_msg() in two parts
> irqchip/gicv2m: Don't map the MSI page in gicv2m_compose_msi_msg()
> irqchip/gic-v3-its: Don't map the MSI page in
> its_irq_compose_msi_msg()
> irqchip/ls-scfg-msi: Don't map the MSI page in
> ls_scfg_msi_compose_msg()
> irqchip/gic-v3-mbi: Don't map the MSI page in mbi_compose_m{b,
> s}i_msg()
> iommu/dma-iommu: Remove iommu_dma_map_msi_msg()
>
> drivers/iommu/Kconfig | 1 +
> drivers/iommu/dma-iommu.c | 49 +++++++++++++++++++++++----------------
> drivers/irqchip/irq-gic-v2m.c | 8 ++++++-
> drivers/irqchip/irq-gic-v3-its.c | 5 +++-
> drivers/irqchip/irq-gic-v3-mbi.c | 15 ++++++++++--
> drivers/irqchip/irq-ls-scfg-msi.c | 7 +++++-
> include/linux/dma-iommu.h | 22 ++++++++++++++++--
> include/linux/msi.h | 26 +++++++++++++++++++++
> kernel/irq/Kconfig | 3 +++
> 9 files changed, 109 insertions(+), 27 deletions(-)
Thanks for having reworked this. I'm quite happy with the way this looks
now (modulo the couple of nits Robin and I mentioned, which I'm to
address myself).
Jorg: are you OK with this going via the irq tree?
Thanks,
M.
--
Jazz is not dead. It just smells funny...
