| Message ID | 20221111122013.888850936@linutronix.de (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | genirq, PCI/MSI: Support for per device MSI and PCI/IMS - Part 1 cleanups | expand |
On Fri, Nov 11, 2022 at 02:54:22PM +0100, Thomas Gleixner wrote: > When a range of descriptors is freed then all of them are not associated to > a linux interrupt. Remove the filter and add a warning to the free function. > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > --- > drivers/base/platform-msi.c | 2 +- > include/linux/msi.h | 5 ++--- > kernel/irq/msi.c | 19 ++++++++++--------- > 3 files changed, 13 insertions(+), 13 deletions(-) Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Jason
Hi Thomas, tglx@linutronix.de wrote on Fri, 11 Nov 2022 14:54:22 +0100 (CET): > When a range of descriptors is freed then all of them are not associated to > a linux interrupt. Remove the filter and add a warning to the free function. > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > --- [...] > --- a/kernel/irq/msi.c > +++ b/kernel/irq/msi.c > @@ -120,7 +120,7 @@ static int msi_add_simple_msi_descs(stru > fail_mem: > ret = -ENOMEM; > fail: > - msi_free_msi_descs_range(dev, MSI_DESC_ALL, index, last); > + msi_free_msi_descs_range(dev, index, last); > return ret; > } > > @@ -141,12 +141,11 @@ static bool msi_desc_match(struct msi_de > /** > * msi_free_msi_descs_range - Free MSI descriptors of a device > * @dev: Device to free the descriptors > - * @filter: Descriptor state filter > * @first_index: Index to start freeing from > * @last_index: Last index to be freed > */ > -void msi_free_msi_descs_range(struct device *dev, enum msi_desc_filter filter, > - unsigned int first_index, unsigned int last_index) > +void msi_free_msi_descs_range(struct device *dev, unsigned int first_index, > + unsigned int last_index) > { > struct xarray *xa = &dev->msi.data->__store; > struct msi_desc *desc; > @@ -155,10 +154,12 @@ void msi_free_msi_descs_range(struct dev > lockdep_assert_held(&dev->msi.data->mutex); > > xa_for_each_range(xa, idx, desc, first_index, last_index) { > - if (msi_desc_match(desc, filter)) { > - xa_erase(xa, idx); > - msi_free_desc(desc); > - } > + xa_erase(xa, idx); > + > + /* Leak the descriptor when it is still referenced */ > + if (WARN_ON_ONCE(msi_desc_match(desc, MSI_DESC_ASSOCIATED))) > + continue; > + msi_free_desc(desc); > } > } It looks like since this commit I am getting warnings upon EPROBE_DEFER errors in the mvpp2 Marvell Ethernet driver. I looked a bit at the internals to understand why this warning was shown, and it seems that nothing "de-references" the descriptors, which would mean here: resetting desc->irq to 0. In my case I don't think the mvpp2_main.c driver nor the irq_mvebu_icu.c driver behind do anything strange (as far as I understand them). I believe any error during a ->probe() leading to an irq_dispose_mapping() call with MSI behind will trigger that warning. I am wondering how useful thisd WARN_ON() is, or otherwise where the desc->irq entry should be zeroed (if I understand that correctly), any help will be appreciated. Here is the splat: [ 2.045857] ------------[ cut here ]------------ [ 2.050497] WARNING: CPU: 2 PID: 9 at kernel/irq/msi.c:197 msi_domain_free_descs+0x120/0x128 [ 2.058993] Modules linked in: [ 2.062068] CPU: 2 PID: 9 Comm: kworker/u8:0 Not tainted 6.2.0-rc1+ #168 [ 2.068804] Hardware name: Delta TN48M (DT) [ 2.073008] Workqueue: events_unbound deferred_probe_work_func [ 2.078878] pstate: 00000005 (nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 2.085875] pc : msi_domain_free_descs+0x120/0x128 [ 2.090693] lr : msi_domain_free_descs+0xe0/0x128 [ 2.095423] sp : ffff80000a82b8d0 [ 2.098745] x29: ffff80000a82b8d0 x28: 00007bfdbb508ca8 x27: ffff000102e28940 [ 2.105921] x26: 0000000000000004 x25: ffff000100257660 x24: ffff800009a6b8d8 [ 2.113096] x23: ffff800008a1c868 x22: ffff000102e4b700 x21: ffff000101494bb0 [ 2.120270] x20: ffff80000a82b958 x19: ffff800009afe248 x18: 0000000000000010 [ 2.127444] x17: fffffc0000fa4008 x16: 0000000000000008 x15: 000000000000013a [ 2.134618] x14: ffff80000a82b6a0 x13: 00000000ffffffea x12: ffff80000a82b870 [ 2.141794] x11: 0000000000000002 x10: 0000000000000000 x9 : 0000000000000001 [ 2.148967] x8 : 0000000000000000 x7 : 0000000000000238 x6 : ffff0001005f1230 [ 2.156141] x5 : 0000000000000000 x4 : 0000200000000000 x3 : 0000000000000000 [ 2.163315] x2 : b586accf01c45400 x1 : ffff0001000e0000 x0 : 000000000000002d [ 2.170489] Call trace: [ 2.172948] msi_domain_free_descs+0x120/0x128 [ 2.177417] msi_domain_free_msi_descs_range+0x64/0x9c [ 2.182586] platform_msi_device_domain_free+0x88/0xb8 [ 2.187752] mvebu_icu_irq_domain_free+0x60/0x80 [ 2.192396] irq_domain_free_irqs_hierarchy.part.21+0x94/0xa8 [ 2.198173] irq_domain_free_irqs+0xec/0x150 [ 2.202466] irq_dispose_mapping+0x104/0x120 [ 2.206758] mvpp2_probe+0x2028/0x21f8 [ 2.210530] platform_probe+0x68/0xd8 [ 2.214210] really_probe+0xbc/0x2a8 [ 2.217807] __driver_probe_device+0x78/0xe0 [ 2.222102] driver_probe_device+0x3c/0x108 [ 2.226308] __device_attach_driver+0xb8/0xf8 [ 2.230690] bus_for_each_drv+0x7c/0xd0 [ 2.234547] __device_attach+0xec/0x188 [ 2.238404] device_initial_probe+0x14/0x20 [ 2.242611] bus_probe_device+0x9c/0xa8 [ 2.246468] deferred_probe_work_func+0x88/0xc0 [ 2.251024] process_one_work+0x1fc/0x348 [ 2.255056] worker_thread+0x228/0x420 [ 2.258825] kthread+0x10c/0x118 [ 2.262075] ret_from_fork+0x10/0x20 [ 2.265672] ---[ end trace 0000000000000000 ]--- Thanks, Miquèl
Miquel! On Wed, Mar 01 2023 at 11:55, Miquel Raynal wrote: > tglx@linutronix.de wrote on Fri, 11 Nov 2022 14:54:22 +0100 (CET): > >> When a range of descriptors is freed then all of them are not associated to >> a linux interrupt. Remove the filter and add a warning to the free function. >> + /* Leak the descriptor when it is still referenced */ >> + if (WARN_ON_ONCE(msi_desc_match(desc, MSI_DESC_ASSOCIATED))) >> + continue; >> + msi_free_desc(desc); >> } >> } > > It looks like since this commit I am getting warnings upon EPROBE_DEFER > errors in the mvpp2 Marvell Ethernet driver. I looked a bit at the > internals to understand why this warning was shown, and it seems that > nothing "de-references" the descriptors, which would mean here: > resetting desc->irq to 0. Correct. This platform-msi ^(*&!@&^ hack really needs to die ASAP. Marc, where are we on that? Is this still in limbo? > I am wondering how useful thisd WARN_ON() is, or otherwise where the It is useful as it caught bugs already. > desc->irq entry should be zeroed (if I understand that correctly), any > help will be appreciated. Untested workaround below. I hate it with a passion, but *shrug*. Thanks, tglx --- drivers/base/platform-msi.c | 1 + include/linux/msi.h | 2 ++ kernel/irq/msi.c | 23 ++++++++++++++++++++++- 3 files changed, 25 insertions(+), 1 deletion(-) --- a/drivers/base/platform-msi.c +++ b/drivers/base/platform-msi.c @@ -324,6 +324,7 @@ void platform_msi_device_domain_free(str struct platform_msi_priv_data *data = domain->host_data; msi_lock_descs(data->dev); + msi_domain_depopulate_descs(data->dev, virq, nr_irqs); irq_domain_free_irqs_common(domain, virq, nr_irqs); msi_free_msi_descs_range(data->dev, virq, virq + nr_irqs - 1); msi_unlock_descs(data->dev); --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -631,6 +631,8 @@ int msi_domain_prepare_irqs(struct irq_d int nvec, msi_alloc_info_t *args); int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev, int virq, int nvec, msi_alloc_info_t *args); +void msi_domain_depopulate_descs(struct device *dev, int virq, int nvec); + struct irq_domain * __platform_msi_create_device_domain(struct device *dev, unsigned int nvec, --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -1109,14 +1109,35 @@ int msi_domain_populate_irqs(struct irq_ return 0; fail: - for (--virq; virq >= virq_base; virq--) + for (--virq; virq >= virq_base; virq--) { + msi_domain_depopulate_descs(dev, virq, 1); irq_domain_free_irqs_common(domain, virq, 1); + } msi_domain_free_descs(dev, &ctrl); unlock: msi_unlock_descs(dev); return ret; } +void msi_domain_depopulate_descs(struct device *dev, int virq_base, int nvec) +{ + struct msi_ctrl ctrl = { + .domid = MSI_DEFAULT_DOMAIN, + .first = virq_base, + .last = virq_base + nvec - 1, + }; + struct msi_desc *desc; + struct xarray *xa; + unsigned long idx; + + if (!msi_ctrl_valid(dev, &ctrl)) + return; + + xa = &dev->msi.data->__domains[ctrl.domid].store; + xa_for_each_range(xa, idx, desc, ctrl.first, ctrl.last) + desc->irq = 0; +} + /* * Carefully check whether the device can use reservation mode. If * reservation mode is enabled then the early activation will assign a
Hi Thomas, tglx@linutronix.de wrote on Wed, 01 Mar 2023 22:07:48 +0100: > Miquel! > > On Wed, Mar 01 2023 at 11:55, Miquel Raynal wrote: > > tglx@linutronix.de wrote on Fri, 11 Nov 2022 14:54:22 +0100 (CET): > > > >> When a range of descriptors is freed then all of them are not associated to > >> a linux interrupt. Remove the filter and add a warning to the free function. > >> + /* Leak the descriptor when it is still referenced */ > >> + if (WARN_ON_ONCE(msi_desc_match(desc, MSI_DESC_ASSOCIATED))) > >> + continue; > >> + msi_free_desc(desc); > >> } > >> } > > > > It looks like since this commit I am getting warnings upon EPROBE_DEFER > > errors in the mvpp2 Marvell Ethernet driver. I looked a bit at the > > internals to understand why this warning was shown, and it seems that > > nothing "de-references" the descriptors, which would mean here: > > resetting desc->irq to 0. > > Correct. This platform-msi ^(*&!@&^ hack really needs to die ASAP. :-) > Marc, where are we on that? Is this still in limbo? > > > I am wondering how useful thisd WARN_ON() is, or otherwise where the > > It is useful as it caught bugs already. Sure. > > desc->irq entry should be zeroed (if I understand that correctly), any > > help will be appreciated. > > Untested workaround below. Excellent! > I hate it with a passion, but *shrug*. :'D > Thanks, > > tglx > --- > drivers/base/platform-msi.c | 1 + > include/linux/msi.h | 2 ++ > kernel/irq/msi.c | 23 ++++++++++++++++++++++- > 3 files changed, 25 insertions(+), 1 deletion(-) Kudos for the diff, which indeed works perfectly in my case. I guess you'll make a proper patch soon, if that's the case you can add my: Tested-by: Miquel Raynal <miquel.raynal@bootlin.com> Let me know otherwise. Thanks a lot for the very quick fix! Miquèl > --- a/drivers/base/platform-msi.c > +++ b/drivers/base/platform-msi.c > @@ -324,6 +324,7 @@ void platform_msi_device_domain_free(str > struct platform_msi_priv_data *data = domain->host_data; > > msi_lock_descs(data->dev); > + msi_domain_depopulate_descs(data->dev, virq, nr_irqs); > irq_domain_free_irqs_common(domain, virq, nr_irqs); > msi_free_msi_descs_range(data->dev, virq, virq + nr_irqs - 1); > msi_unlock_descs(data->dev); > --- a/include/linux/msi.h > +++ b/include/linux/msi.h > @@ -631,6 +631,8 @@ int msi_domain_prepare_irqs(struct irq_d > int nvec, msi_alloc_info_t *args); > int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev, > int virq, int nvec, msi_alloc_info_t *args); > +void msi_domain_depopulate_descs(struct device *dev, int virq, int nvec); > + > struct irq_domain * > __platform_msi_create_device_domain(struct device *dev, > unsigned int nvec, > --- a/kernel/irq/msi.c > +++ b/kernel/irq/msi.c > @@ -1109,14 +1109,35 @@ int msi_domain_populate_irqs(struct irq_ > return 0; > > fail: > - for (--virq; virq >= virq_base; virq--) > + for (--virq; virq >= virq_base; virq--) { > + msi_domain_depopulate_descs(dev, virq, 1); > irq_domain_free_irqs_common(domain, virq, 1); > + } > msi_domain_free_descs(dev, &ctrl); > unlock: > msi_unlock_descs(dev); > return ret; > } > > +void msi_domain_depopulate_descs(struct device *dev, int virq_base, int nvec) > +{ > + struct msi_ctrl ctrl = { > + .domid = MSI_DEFAULT_DOMAIN, > + .first = virq_base, > + .last = virq_base + nvec - 1, > + }; > + struct msi_desc *desc; > + struct xarray *xa; > + unsigned long idx; > + > + if (!msi_ctrl_valid(dev, &ctrl)) > + return; > + > + xa = &dev->msi.data->__domains[ctrl.domid].store; > + xa_for_each_range(xa, idx, desc, ctrl.first, ctrl.last) > + desc->irq = 0; > +} > + > /* > * Carefully check whether the device can use reservation mode. If > * reservation mode is enabled then the early activation will assign a
--- a/drivers/base/platform-msi.c +++ b/drivers/base/platform-msi.c @@ -325,7 +325,7 @@ void platform_msi_device_domain_free(str msi_lock_descs(data->dev); irq_domain_free_irqs_common(domain, virq, nr_irqs); - msi_free_msi_descs_range(data->dev, MSI_DESC_ALL, virq, virq + nr_irqs - 1); + msi_free_msi_descs_range(data->dev, virq, virq + nr_irqs - 1); msi_unlock_descs(data->dev); } --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -247,8 +247,7 @@ static inline void pci_write_msi_msg(uns #endif /* CONFIG_PCI_MSI */ int msi_add_msi_desc(struct device *dev, struct msi_desc *init_desc); -void msi_free_msi_descs_range(struct device *dev, enum msi_desc_filter filter, - unsigned int first_index, unsigned int last_index); +void msi_free_msi_descs_range(struct device *dev, unsigned int first_index, unsigned int last_index); /** * msi_free_msi_descs - Free MSI descriptors of a device @@ -256,7 +255,7 @@ void msi_free_msi_descs_range(struct dev */ static inline void msi_free_msi_descs(struct device *dev) { - msi_free_msi_descs_range(dev, MSI_DESC_ALL, 0, MSI_MAX_INDEX); + msi_free_msi_descs_range(dev, 0, MSI_MAX_INDEX); } void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg); --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -120,7 +120,7 @@ static int msi_add_simple_msi_descs(stru fail_mem: ret = -ENOMEM; fail: - msi_free_msi_descs_range(dev, MSI_DESC_ALL, index, last); + msi_free_msi_descs_range(dev, index, last); return ret; } @@ -141,12 +141,11 @@ static bool msi_desc_match(struct msi_de /** * msi_free_msi_descs_range - Free MSI descriptors of a device * @dev: Device to free the descriptors - * @filter: Descriptor state filter * @first_index: Index to start freeing from * @last_index: Last index to be freed */ -void msi_free_msi_descs_range(struct device *dev, enum msi_desc_filter filter, - unsigned int first_index, unsigned int last_index) +void msi_free_msi_descs_range(struct device *dev, unsigned int first_index, + unsigned int last_index) { struct xarray *xa = &dev->msi.data->__store; struct msi_desc *desc; @@ -155,10 +154,12 @@ void msi_free_msi_descs_range(struct dev lockdep_assert_held(&dev->msi.data->mutex); xa_for_each_range(xa, idx, desc, first_index, last_index) { - if (msi_desc_match(desc, filter)) { - xa_erase(xa, idx); - msi_free_desc(desc); - } + xa_erase(xa, idx); + + /* Leak the descriptor when it is still referenced */ + if (WARN_ON_ONCE(msi_desc_match(desc, MSI_DESC_ASSOCIATED))) + continue; + msi_free_desc(desc); } } @@ -739,7 +740,7 @@ int msi_domain_populate_irqs(struct irq_ fail: for (--virq; virq >= virq_base; virq--) irq_domain_free_irqs_common(domain, virq, 1); - msi_free_msi_descs_range(dev, MSI_DESC_ALL, virq_base, virq_base + nvec - 1); + msi_free_msi_descs_range(dev, virq_base, virq_base + nvec - 1); unlock: msi_unlock_descs(dev); return ret;
When a range of descriptors is freed then all of them are not associated to a linux interrupt. Remove the filter and add a warning to the free function. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> --- drivers/base/platform-msi.c | 2 +- include/linux/msi.h | 5 ++--- kernel/irq/msi.c | 19 ++++++++++--------- 3 files changed, 13 insertions(+), 13 deletions(-)