Re: [PATCH] PCI: Don't use Printk in raw_spinlocks
On 2020-09-10 13:46:27, Bjorn Helgaas wrote:
> On Thu, Sep 10, 2020 at 08:21:06AM -0600, Rob Herring wrote:
> > On Wed, Sep 9, 2020 at 8:07 PM Bjorn Helgaas wrote:
> > >
> > > [+cc Mark, Florian, Rob, Scott]
> > >
> > > On Sat, Aug 01, 2020 at 09:25:49AM +0800, Xingxing Su wrote:
> > > > Do not use printk in raw_spinlocks,
> > > > it will cause BUG: Invalid wait context.
> > > >
> > > > The trace reported by lockdep follows.
> > > >
> > > > [2.986113] =
> > > > [2.986115] [ BUG: Invalid wait context ]
> > > > [2.986116] 5.8.0-rc1+ #11 Not tainted
> > > > [2.986118] -
> > > > [2.986120] swapper/0/1 is trying to lock:
> > > > [2.986122] 80f5ddd8 (console_owner){}-{3:3}, at:
> > > > console_unlock+0x284/0x820
> > > > [2.986130] other info that might help us debug this:
> > > > [2.986132] context-{5:5}
> > > > [2.986134] 3 locks held by swapper/0/1:
> > > > [2.986135] #0: 9807fa03c990 (>mutex){}-{0:0}, at:
> > > > device_driver_attach+0x28/0x90
> > > > [2.986144] #1: 80fb83a8 (pci_lock){}-{2:2}, at:
> > > > pci_bus_write_config_word+0x60/0xb8
> > > > [2.986152] #2: 80f5ded0 (console_lock){+.+.}-{0:0}, at:
> > > > vprintk_emit+0x1b0/0x3b8
> > > > [2.986161] stack backtrace:
> > > > [2.986163] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #11
> > > > [2.986164] Stack : 1d67 9800030be9b0
> > > > 0001 7b2aba74f6c4785b
> > > > [2.986172] 7b2aba74f6c4785b
> > > > 9807f89cb438 80e7dc80
> > > > [2.986181] 0001 000a
> > > > 0001 0001
> > > > [2.986189] 80f4e156 fffd
> > > > 80cc2d98 f800
> > > > [2.986197] 2400 80f4
> > > >
> > > > [2.986205] 9500cce0
> > > > 80f5 81546318
> > > > [2.986213] 81c4c3c0 0018
> > > > bc00
> > > > [2.986221] 8134 9807f89c8000
> > > > 9807f89cb430 9807f8a0
> > > > [2.986229] 806be568
> > > >
> > > > [2.986237]
> > > > 80211c1c 7b2aba74f6c4785b
> > > > [2.986245] ...
> > > > [2.986250] Call Trace:
> > > > [2.986251] [] show_stack+0x9c/0x130
> > > > [2.986253] [] dump_stack+0xe8/0x150
> > > > [2.986255] [] __lock_acquire+0x570/0x3250
> > > > [2.986257] [] lock_acquire+0x118/0x558
> > > > [2.986259] [] console_unlock+0x2e4/0x820
> > > > [2.986261] [] vprintk_emit+0x1c0/0x3b8
> > > > [2.986263] [] dev_vprintk_emit+0x1c8/0x210
> > > > [2.986265] [] dev_printk_emit+0x3c/0x60
> > > > [2.986267] [] _dev_warn+0x5c/0x80
> > > > [2.986269] []
> > > > pci_generic_config_write32+0x154/0x160
> > > > [2.986271] [] pci_bus_write_config_word+0x84/0xb8
> > > > [2.986273] [] pci_setup_device+0x22c/0x768
> > > > [2.986275] [] pci_scan_single_device+0xc8/0x100
> > > > [2.986277] [] pci_scan_slot+0xb0/0x178
> > > > [2.986279] [] pci_scan_child_bus_extend+0x5c/0x370
> > > > [2.986281] [] pci_scan_root_bus_bridge+0x6c/0xf0
> > > > [2.986283] [] pci_host_probe+0x1c/0xd8
> > > > [2.986285] [] platform_drv_probe+0x54/0xb8
> > > > [2.986287] [] really_probe+0x130/0x388
> > > > [2.986289] [] driver_probe_device+0x64/0xd8
> > > > [2.986291] [] device_driver_attach+0x84/0x90
> > > > [2.986293] [] __driver_attach+0xc8/0x128
> > > > [2.986295] [] bus_for_each_dev+0x74/0xd8
> > > > [2.986297] [] bus_add_driver+0x170/0x250
> > > > [2.986299] [] driver_register+0x84/0x150
> > > > [2.986301] [] do_one_initcall+0x98/0x458
> > > > [2.986303] [] kernel_init_freeable+0x2c0/0x36c
> > > > [2.986305] [] kernel_init+0x10/0x128
> > > > [2.986307] [] ret_from_kernel_thread+0x14/0x1c
> > > >
> > > > Signed-off-by: Xingxing Su
> > > > ---
> > > > drivers/pci/access.c | 3 ---
> > > > 1 file changed, 3 deletions(-)
> > > >
> > > > diff --git a/drivers/pci/access.c b/drivers/pci/access.c
> > > > index 79c4a2e..b3fc164 100644
> > > > --- a/drivers/pci/access.c
> > > > +++ b/drivers/pci/access.c
> > > > @@ -160,9 +160,6 @@ int pci_generic_config_write32(struct pci_bus *bus,
> > > > unsigned int devfn,
> > > >* write happen to have any RW1C (write-one-to-clear) bits set, we
> > > >* just inadvertently cleared something we shouldn't have.
> > > >*/
> > > > - dev_warn_ratelimited(>dev, "%d-byte config write to
> > > > %04x:%02x:%02x.%d offset %#x may corrupt adjacent RW1C bits\n",
> > > > - size, pci_domain_nr(bus), bus->number,
> > > > -
Re: [PATCH] PCI: Don't use Printk in raw_spinlocks
On Wed, Sep 9, 2020 at 8:07 PM Bjorn Helgaas wrote:
>
> [+cc Mark, Florian, Rob, Scott]
>
> On Sat, Aug 01, 2020 at 09:25:49AM +0800, Xingxing Su wrote:
> > Do not use printk in raw_spinlocks,
> > it will cause BUG: Invalid wait context.
> >
> > The trace reported by lockdep follows.
> >
> > [2.986113] =
> > [2.986115] [ BUG: Invalid wait context ]
> > [2.986116] 5.8.0-rc1+ #11 Not tainted
> > [2.986118] -
> > [2.986120] swapper/0/1 is trying to lock:
> > [2.986122] 80f5ddd8 (console_owner){}-{3:3}, at:
> > console_unlock+0x284/0x820
> > [2.986130] other info that might help us debug this:
> > [2.986132] context-{5:5}
> > [2.986134] 3 locks held by swapper/0/1:
> > [2.986135] #0: 9807fa03c990 (>mutex){}-{0:0}, at:
> > device_driver_attach+0x28/0x90
> > [2.986144] #1: 80fb83a8 (pci_lock){}-{2:2}, at:
> > pci_bus_write_config_word+0x60/0xb8
> > [2.986152] #2: 80f5ded0 (console_lock){+.+.}-{0:0}, at:
> > vprintk_emit+0x1b0/0x3b8
> > [2.986161] stack backtrace:
> > [2.986163] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #11
> > [2.986164] Stack : 1d67 9800030be9b0 0001
> > 7b2aba74f6c4785b
> > [2.986172] 7b2aba74f6c4785b 9807f89cb438
> > 80e7dc80
> > [2.986181] 0001 000a 0001
> > 0001
> > [2.986189] 80f4e156 fffd 80cc2d98
> > f800
> > [2.986197] 2400 80f4
> >
> > [2.986205] 9500cce0 80f5
> > 81546318
> > [2.986213] 81c4c3c0 0018 bc00
> >
> > [2.986221] 8134 9807f89c8000 9807f89cb430
> > 9807f8a0
> > [2.986229] 806be568
> >
> > [2.986237] 80211c1c
> > 7b2aba74f6c4785b
> > [2.986245] ...
> > [2.986250] Call Trace:
> > [2.986251] [] show_stack+0x9c/0x130
> > [2.986253] [] dump_stack+0xe8/0x150
> > [2.986255] [] __lock_acquire+0x570/0x3250
> > [2.986257] [] lock_acquire+0x118/0x558
> > [2.986259] [] console_unlock+0x2e4/0x820
> > [2.986261] [] vprintk_emit+0x1c0/0x3b8
> > [2.986263] [] dev_vprintk_emit+0x1c8/0x210
> > [2.986265] [] dev_printk_emit+0x3c/0x60
> > [2.986267] [] _dev_warn+0x5c/0x80
> > [2.986269] [] pci_generic_config_write32+0x154/0x160
> > [2.986271] [] pci_bus_write_config_word+0x84/0xb8
> > [2.986273] [] pci_setup_device+0x22c/0x768
> > [2.986275] [] pci_scan_single_device+0xc8/0x100
> > [2.986277] [] pci_scan_slot+0xb0/0x178
> > [2.986279] [] pci_scan_child_bus_extend+0x5c/0x370
> > [2.986281] [] pci_scan_root_bus_bridge+0x6c/0xf0
> > [2.986283] [] pci_host_probe+0x1c/0xd8
> > [2.986285] [] platform_drv_probe+0x54/0xb8
> > [2.986287] [] really_probe+0x130/0x388
> > [2.986289] [] driver_probe_device+0x64/0xd8
> > [2.986291] [] device_driver_attach+0x84/0x90
> > [2.986293] [] __driver_attach+0xc8/0x128
> > [2.986295] [] bus_for_each_dev+0x74/0xd8
> > [2.986297] [] bus_add_driver+0x170/0x250
> > [2.986299] [] driver_register+0x84/0x150
> > [2.986301] [] do_one_initcall+0x98/0x458
> > [2.986303] [] kernel_init_freeable+0x2c0/0x36c
> > [2.986305] [] kernel_init+0x10/0x128
> > [2.986307] [] ret_from_kernel_thread+0x14/0x1c
> >
> > Signed-off-by: Xingxing Su
> > ---
> > drivers/pci/access.c | 3 ---
> > 1 file changed, 3 deletions(-)
> >
> > diff --git a/drivers/pci/access.c b/drivers/pci/access.c
> > index 79c4a2e..b3fc164 100644
> > --- a/drivers/pci/access.c
> > +++ b/drivers/pci/access.c
> > @@ -160,9 +160,6 @@ int pci_generic_config_write32(struct pci_bus *bus,
> > unsigned int devfn,
> >* write happen to have any RW1C (write-one-to-clear) bits set, we
> >* just inadvertently cleared something we shouldn't have.
> >*/
> > - dev_warn_ratelimited(>dev, "%d-byte config write to
> > %04x:%02x:%02x.%d offset %#x may corrupt adjacent RW1C bits\n",
> > - size, pci_domain_nr(bus), bus->number,
> > - PCI_SLOT(devfn), PCI_FUNC(devfn), where);
>
> We just changed this printk (see [1]), but I think we still have this
> lockdep problem even after Mark's change. So I guess we need another
> think about this.
>
> Maybe we can print something when registering pci_ops that use
> pci_generic_config_write32()?
That was my suggestion, but as Mark pointed out that doesn't work if
pci_generic_config_write32 is wrapped (which is 4 out of 8 cases).
Also, 3 of the cases are only for the root bus (bridge).
Re: [PATCH] PCI: Don't use Printk in raw_spinlocks
On 9/10/2020 12:20 PM, Bjorn Helgaas wrote:
On Thu, Sep 10, 2020 at 11:50:07AM -0700, Florian Fainelli wrote:
On 9/10/2020 11:46 AM, Bjorn Helgaas wrote:
On Thu, Sep 10, 2020 at 08:21:06AM -0600, Rob Herring wrote:
On Wed, Sep 9, 2020 at 8:07 PM Bjorn Helgaas wrote:
[+cc Mark, Florian, Rob, Scott]
On Sat, Aug 01, 2020 at 09:25:49AM +0800, Xingxing Su wrote:
Do not use printk in raw_spinlocks,
it will cause BUG: Invalid wait context.
The trace reported by lockdep follows.
[2.986113] =
[2.986115] [ BUG: Invalid wait context ]
[2.986116] 5.8.0-rc1+ #11 Not tainted
[2.986118] -
[2.986120] swapper/0/1 is trying to lock:
[2.986122] 80f5ddd8 (console_owner){}-{3:3}, at:
console_unlock+0x284/0x820
[2.986130] other info that might help us debug this:
[2.986132] context-{5:5}
[2.986134] 3 locks held by swapper/0/1:
[2.986135] #0: 9807fa03c990 (>mutex){}-{0:0}, at:
device_driver_attach+0x28/0x90
[2.986144] #1: 80fb83a8 (pci_lock){}-{2:2}, at:
pci_bus_write_config_word+0x60/0xb8
[2.986152] #2: 80f5ded0 (console_lock){+.+.}-{0:0}, at:
vprintk_emit+0x1b0/0x3b8
[2.986161] stack backtrace:
[2.986163] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #11
[2.986164] Stack : 1d67 9800030be9b0 0001
7b2aba74f6c4785b
[2.986172] 7b2aba74f6c4785b 9807f89cb438
80e7dc80
[2.986181] 0001 000a 0001
0001
[2.986189] 80f4e156 fffd 80cc2d98
f800
[2.986197] 2400 80f4
[2.986205] 9500cce0 80f5
81546318
[2.986213] 81c4c3c0 0018 bc00
[2.986221] 8134 9807f89c8000 9807f89cb430
9807f8a0
[2.986229] 806be568
[2.986237] 80211c1c
7b2aba74f6c4785b
[2.986245] ...
[2.986250] Call Trace:
[2.986251] [] show_stack+0x9c/0x130
[2.986253] [] dump_stack+0xe8/0x150
[2.986255] [] __lock_acquire+0x570/0x3250
[2.986257] [] lock_acquire+0x118/0x558
[2.986259] [] console_unlock+0x2e4/0x820
[2.986261] [] vprintk_emit+0x1c0/0x3b8
[2.986263] [] dev_vprintk_emit+0x1c8/0x210
[2.986265] [] dev_printk_emit+0x3c/0x60
[2.986267] [] _dev_warn+0x5c/0x80
[2.986269] [] pci_generic_config_write32+0x154/0x160
[2.986271] [] pci_bus_write_config_word+0x84/0xb8
[2.986273] [] pci_setup_device+0x22c/0x768
[2.986275] [] pci_scan_single_device+0xc8/0x100
[2.986277] [] pci_scan_slot+0xb0/0x178
[2.986279] [] pci_scan_child_bus_extend+0x5c/0x370
[2.986281] [] pci_scan_root_bus_bridge+0x6c/0xf0
[2.986283] [] pci_host_probe+0x1c/0xd8
[2.986285] [] platform_drv_probe+0x54/0xb8
[2.986287] [] really_probe+0x130/0x388
[2.986289] [] driver_probe_device+0x64/0xd8
[2.986291] [] device_driver_attach+0x84/0x90
[2.986293] [] __driver_attach+0xc8/0x128
[2.986295] [] bus_for_each_dev+0x74/0xd8
[2.986297] [] bus_add_driver+0x170/0x250
[2.986299] [] driver_register+0x84/0x150
[2.986301] [] do_one_initcall+0x98/0x458
[2.986303] [] kernel_init_freeable+0x2c0/0x36c
[2.986305] [] kernel_init+0x10/0x128
[2.986307] [] ret_from_kernel_thread+0x14/0x1c
Signed-off-by: Xingxing Su
---
drivers/pci/access.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 79c4a2e..b3fc164 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -160,9 +160,6 @@ int pci_generic_config_write32(struct pci_bus *bus,
unsigned int devfn,
* write happen to have any RW1C (write-one-to-clear) bits set, we
* just inadvertently cleared something we shouldn't have.
*/
- dev_warn_ratelimited(>dev, "%d-byte config write to %04x:%02x:%02x.%d
offset %#x may corrupt adjacent RW1C bits\n",
- size, pci_domain_nr(bus), bus->number,
- PCI_SLOT(devfn), PCI_FUNC(devfn), where);
We just changed this printk (see [1]), but I think we still have this
lockdep problem even after Mark's change. So I guess we need another
think about this.
Maybe we can print something when registering pci_ops that use
pci_generic_config_write32()?
That was my suggestion, but as Mark pointed out that doesn't work if
pci_generic_config_write32 is wrapped (which is 4 out of 8 cases).
Also, 3 of the cases are only for the root bus (bridge). Are 32-bit
writes to a bridge going to cause problems? For xgene, interestingly,
with DT _write32 is needed, but for ACPI it is not (only _read32). I
Re: [PATCH] PCI: Don't use Printk in raw_spinlocks
On Thu, Sep 10, 2020 at 11:50:07AM -0700, Florian Fainelli wrote:
> On 9/10/2020 11:46 AM, Bjorn Helgaas wrote:
> > On Thu, Sep 10, 2020 at 08:21:06AM -0600, Rob Herring wrote:
> > > On Wed, Sep 9, 2020 at 8:07 PM Bjorn Helgaas wrote:
> > > >
> > > > [+cc Mark, Florian, Rob, Scott]
> > > >
> > > > On Sat, Aug 01, 2020 at 09:25:49AM +0800, Xingxing Su wrote:
> > > > > Do not use printk in raw_spinlocks,
> > > > > it will cause BUG: Invalid wait context.
> > > > >
> > > > > The trace reported by lockdep follows.
> > > > >
> > > > > [2.986113] =
> > > > > [2.986115] [ BUG: Invalid wait context ]
> > > > > [2.986116] 5.8.0-rc1+ #11 Not tainted
> > > > > [2.986118] -
> > > > > [2.986120] swapper/0/1 is trying to lock:
> > > > > [2.986122] 80f5ddd8 (console_owner){}-{3:3}, at:
> > > > > console_unlock+0x284/0x820
> > > > > [2.986130] other info that might help us debug this:
> > > > > [2.986132] context-{5:5}
> > > > > [2.986134] 3 locks held by swapper/0/1:
> > > > > [2.986135] #0: 9807fa03c990 (>mutex){}-{0:0}, at:
> > > > > device_driver_attach+0x28/0x90
> > > > > [2.986144] #1: 80fb83a8 (pci_lock){}-{2:2}, at:
> > > > > pci_bus_write_config_word+0x60/0xb8
> > > > > [2.986152] #2: 80f5ded0 (console_lock){+.+.}-{0:0}, at:
> > > > > vprintk_emit+0x1b0/0x3b8
> > > > > [2.986161] stack backtrace:
> > > > > [2.986163] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+
> > > > > #11
> > > > > [2.986164] Stack : 1d67 9800030be9b0
> > > > > 0001 7b2aba74f6c4785b
> > > > > [2.986172] 7b2aba74f6c4785b
> > > > > 9807f89cb438 80e7dc80
> > > > > [2.986181] 0001 000a
> > > > > 0001 0001
> > > > > [2.986189] 80f4e156 fffd
> > > > > 80cc2d98 f800
> > > > > [2.986197] 2400 80f4
> > > > >
> > > > > [2.986205] 9500cce0
> > > > > 80f5 81546318
> > > > > [2.986213] 81c4c3c0 0018
> > > > > bc00
> > > > > [2.986221] 8134 9807f89c8000
> > > > > 9807f89cb430 9807f8a0
> > > > > [2.986229] 806be568
> > > > >
> > > > > [2.986237]
> > > > > 80211c1c 7b2aba74f6c4785b
> > > > > [2.986245] ...
> > > > > [2.986250] Call Trace:
> > > > > [2.986251] [] show_stack+0x9c/0x130
> > > > > [2.986253] [] dump_stack+0xe8/0x150
> > > > > [2.986255] [] __lock_acquire+0x570/0x3250
> > > > > [2.986257] [] lock_acquire+0x118/0x558
> > > > > [2.986259] [] console_unlock+0x2e4/0x820
> > > > > [2.986261] [] vprintk_emit+0x1c0/0x3b8
> > > > > [2.986263] [] dev_vprintk_emit+0x1c8/0x210
> > > > > [2.986265] [] dev_printk_emit+0x3c/0x60
> > > > > [2.986267] [] _dev_warn+0x5c/0x80
> > > > > [2.986269] []
> > > > > pci_generic_config_write32+0x154/0x160
> > > > > [2.986271] []
> > > > > pci_bus_write_config_word+0x84/0xb8
> > > > > [2.986273] [] pci_setup_device+0x22c/0x768
> > > > > [2.986275] [] pci_scan_single_device+0xc8/0x100
> > > > > [2.986277] [] pci_scan_slot+0xb0/0x178
> > > > > [2.986279] []
> > > > > pci_scan_child_bus_extend+0x5c/0x370
> > > > > [2.986281] [] pci_scan_root_bus_bridge+0x6c/0xf0
> > > > > [2.986283] [] pci_host_probe+0x1c/0xd8
> > > > > [2.986285] [] platform_drv_probe+0x54/0xb8
> > > > > [2.986287] [] really_probe+0x130/0x388
> > > > > [2.986289] [] driver_probe_device+0x64/0xd8
> > > > > [2.986291] [] device_driver_attach+0x84/0x90
> > > > > [2.986293] [] __driver_attach+0xc8/0x128
> > > > > [2.986295] [] bus_for_each_dev+0x74/0xd8
> > > > > [2.986297] [] bus_add_driver+0x170/0x250
> > > > > [2.986299] [] driver_register+0x84/0x150
> > > > > [2.986301] [] do_one_initcall+0x98/0x458
> > > > > [2.986303] [] kernel_init_freeable+0x2c0/0x36c
> > > > > [2.986305] [] kernel_init+0x10/0x128
> > > > > [2.986307] [] ret_from_kernel_thread+0x14/0x1c
> > > > >
> > > > > Signed-off-by: Xingxing Su
> > > > > ---
> > > > > drivers/pci/access.c | 3 ---
> > > > > 1 file changed, 3 deletions(-)
> > > > >
> > > > > diff --git a/drivers/pci/access.c b/drivers/pci/access.c
> > > > > index 79c4a2e..b3fc164 100644
> > > > > --- a/drivers/pci/access.c
> > > > > +++ b/drivers/pci/access.c
> > > > > @@ -160,9 +160,6 @@ int pci_generic_config_write32(struct pci_bus
> > > > > *bus, unsigned int devfn,
> > > > > * write happen to have any RW1C (write-one-to-clear) bits
> > > > > set, we
> > > > > * just
Re: [PATCH] PCI: Don't use Printk in raw_spinlocks
On 9/10/2020 11:46 AM, Bjorn Helgaas wrote:
On Thu, Sep 10, 2020 at 08:21:06AM -0600, Rob Herring wrote:
On Wed, Sep 9, 2020 at 8:07 PM Bjorn Helgaas wrote:
[+cc Mark, Florian, Rob, Scott]
On Sat, Aug 01, 2020 at 09:25:49AM +0800, Xingxing Su wrote:
Do not use printk in raw_spinlocks,
it will cause BUG: Invalid wait context.
The trace reported by lockdep follows.
[2.986113] =
[2.986115] [ BUG: Invalid wait context ]
[2.986116] 5.8.0-rc1+ #11 Not tainted
[2.986118] -
[2.986120] swapper/0/1 is trying to lock:
[2.986122] 80f5ddd8 (console_owner){}-{3:3}, at:
console_unlock+0x284/0x820
[2.986130] other info that might help us debug this:
[2.986132] context-{5:5}
[2.986134] 3 locks held by swapper/0/1:
[2.986135] #0: 9807fa03c990 (>mutex){}-{0:0}, at:
device_driver_attach+0x28/0x90
[2.986144] #1: 80fb83a8 (pci_lock){}-{2:2}, at:
pci_bus_write_config_word+0x60/0xb8
[2.986152] #2: 80f5ded0 (console_lock){+.+.}-{0:0}, at:
vprintk_emit+0x1b0/0x3b8
[2.986161] stack backtrace:
[2.986163] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #11
[2.986164] Stack : 1d67 9800030be9b0 0001
7b2aba74f6c4785b
[2.986172] 7b2aba74f6c4785b 9807f89cb438
80e7dc80
[2.986181] 0001 000a 0001
0001
[2.986189] 80f4e156 fffd 80cc2d98
f800
[2.986197] 2400 80f4
[2.986205] 9500cce0 80f5
81546318
[2.986213] 81c4c3c0 0018 bc00
[2.986221] 8134 9807f89c8000 9807f89cb430
9807f8a0
[2.986229] 806be568
[2.986237] 80211c1c
7b2aba74f6c4785b
[2.986245] ...
[2.986250] Call Trace:
[2.986251] [] show_stack+0x9c/0x130
[2.986253] [] dump_stack+0xe8/0x150
[2.986255] [] __lock_acquire+0x570/0x3250
[2.986257] [] lock_acquire+0x118/0x558
[2.986259] [] console_unlock+0x2e4/0x820
[2.986261] [] vprintk_emit+0x1c0/0x3b8
[2.986263] [] dev_vprintk_emit+0x1c8/0x210
[2.986265] [] dev_printk_emit+0x3c/0x60
[2.986267] [] _dev_warn+0x5c/0x80
[2.986269] [] pci_generic_config_write32+0x154/0x160
[2.986271] [] pci_bus_write_config_word+0x84/0xb8
[2.986273] [] pci_setup_device+0x22c/0x768
[2.986275] [] pci_scan_single_device+0xc8/0x100
[2.986277] [] pci_scan_slot+0xb0/0x178
[2.986279] [] pci_scan_child_bus_extend+0x5c/0x370
[2.986281] [] pci_scan_root_bus_bridge+0x6c/0xf0
[2.986283] [] pci_host_probe+0x1c/0xd8
[2.986285] [] platform_drv_probe+0x54/0xb8
[2.986287] [] really_probe+0x130/0x388
[2.986289] [] driver_probe_device+0x64/0xd8
[2.986291] [] device_driver_attach+0x84/0x90
[2.986293] [] __driver_attach+0xc8/0x128
[2.986295] [] bus_for_each_dev+0x74/0xd8
[2.986297] [] bus_add_driver+0x170/0x250
[2.986299] [] driver_register+0x84/0x150
[2.986301] [] do_one_initcall+0x98/0x458
[2.986303] [] kernel_init_freeable+0x2c0/0x36c
[2.986305] [] kernel_init+0x10/0x128
[2.986307] [] ret_from_kernel_thread+0x14/0x1c
Signed-off-by: Xingxing Su
---
drivers/pci/access.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 79c4a2e..b3fc164 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -160,9 +160,6 @@ int pci_generic_config_write32(struct pci_bus *bus,
unsigned int devfn,
* write happen to have any RW1C (write-one-to-clear) bits set, we
* just inadvertently cleared something we shouldn't have.
*/
- dev_warn_ratelimited(>dev, "%d-byte config write to %04x:%02x:%02x.%d
offset %#x may corrupt adjacent RW1C bits\n",
- size, pci_domain_nr(bus), bus->number,
- PCI_SLOT(devfn), PCI_FUNC(devfn), where);
We just changed this printk (see [1]), but I think we still have this
lockdep problem even after Mark's change. So I guess we need another
think about this.
Maybe we can print something when registering pci_ops that use
pci_generic_config_write32()?
That was my suggestion, but as Mark pointed out that doesn't work if
pci_generic_config_write32 is wrapped (which is 4 out of 8 cases).
Also, 3 of the cases are only for the root bus (bridge). Are 32-bit
writes to a bridge going to cause problems? For xgene, interestingly,
with DT _write32 is needed, but for ACPI it is not (only _read32). I
think xgene is practically dead though a few people still have
systems, but likely xgene with DT is really dead. The
Re: [PATCH] PCI: Don't use Printk in raw_spinlocks
On Thu, Sep 10, 2020 at 08:21:06AM -0600, Rob Herring wrote:
> On Wed, Sep 9, 2020 at 8:07 PM Bjorn Helgaas wrote:
> >
> > [+cc Mark, Florian, Rob, Scott]
> >
> > On Sat, Aug 01, 2020 at 09:25:49AM +0800, Xingxing Su wrote:
> > > Do not use printk in raw_spinlocks,
> > > it will cause BUG: Invalid wait context.
> > >
> > > The trace reported by lockdep follows.
> > >
> > > [2.986113] =
> > > [2.986115] [ BUG: Invalid wait context ]
> > > [2.986116] 5.8.0-rc1+ #11 Not tainted
> > > [2.986118] -
> > > [2.986120] swapper/0/1 is trying to lock:
> > > [2.986122] 80f5ddd8 (console_owner){}-{3:3}, at:
> > > console_unlock+0x284/0x820
> > > [2.986130] other info that might help us debug this:
> > > [2.986132] context-{5:5}
> > > [2.986134] 3 locks held by swapper/0/1:
> > > [2.986135] #0: 9807fa03c990 (>mutex){}-{0:0}, at:
> > > device_driver_attach+0x28/0x90
> > > [2.986144] #1: 80fb83a8 (pci_lock){}-{2:2}, at:
> > > pci_bus_write_config_word+0x60/0xb8
> > > [2.986152] #2: 80f5ded0 (console_lock){+.+.}-{0:0}, at:
> > > vprintk_emit+0x1b0/0x3b8
> > > [2.986161] stack backtrace:
> > > [2.986163] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #11
> > > [2.986164] Stack : 1d67 9800030be9b0 0001
> > > 7b2aba74f6c4785b
> > > [2.986172] 7b2aba74f6c4785b 9807f89cb438
> > > 80e7dc80
> > > [2.986181] 0001 000a 0001
> > > 0001
> > > [2.986189] 80f4e156 fffd 80cc2d98
> > > f800
> > > [2.986197] 2400 80f4
> > >
> > > [2.986205] 9500cce0 80f5
> > > 81546318
> > > [2.986213] 81c4c3c0 0018 bc00
> > >
> > > [2.986221] 8134 9807f89c8000 9807f89cb430
> > > 9807f8a0
> > > [2.986229] 806be568
> > >
> > > [2.986237] 80211c1c
> > > 7b2aba74f6c4785b
> > > [2.986245] ...
> > > [2.986250] Call Trace:
> > > [2.986251] [] show_stack+0x9c/0x130
> > > [2.986253] [] dump_stack+0xe8/0x150
> > > [2.986255] [] __lock_acquire+0x570/0x3250
> > > [2.986257] [] lock_acquire+0x118/0x558
> > > [2.986259] [] console_unlock+0x2e4/0x820
> > > [2.986261] [] vprintk_emit+0x1c0/0x3b8
> > > [2.986263] [] dev_vprintk_emit+0x1c8/0x210
> > > [2.986265] [] dev_printk_emit+0x3c/0x60
> > > [2.986267] [] _dev_warn+0x5c/0x80
> > > [2.986269] [] pci_generic_config_write32+0x154/0x160
> > > [2.986271] [] pci_bus_write_config_word+0x84/0xb8
> > > [2.986273] [] pci_setup_device+0x22c/0x768
> > > [2.986275] [] pci_scan_single_device+0xc8/0x100
> > > [2.986277] [] pci_scan_slot+0xb0/0x178
> > > [2.986279] [] pci_scan_child_bus_extend+0x5c/0x370
> > > [2.986281] [] pci_scan_root_bus_bridge+0x6c/0xf0
> > > [2.986283] [] pci_host_probe+0x1c/0xd8
> > > [2.986285] [] platform_drv_probe+0x54/0xb8
> > > [2.986287] [] really_probe+0x130/0x388
> > > [2.986289] [] driver_probe_device+0x64/0xd8
> > > [2.986291] [] device_driver_attach+0x84/0x90
> > > [2.986293] [] __driver_attach+0xc8/0x128
> > > [2.986295] [] bus_for_each_dev+0x74/0xd8
> > > [2.986297] [] bus_add_driver+0x170/0x250
> > > [2.986299] [] driver_register+0x84/0x150
> > > [2.986301] [] do_one_initcall+0x98/0x458
> > > [2.986303] [] kernel_init_freeable+0x2c0/0x36c
> > > [2.986305] [] kernel_init+0x10/0x128
> > > [2.986307] [] ret_from_kernel_thread+0x14/0x1c
> > >
> > > Signed-off-by: Xingxing Su
> > > ---
> > > drivers/pci/access.c | 3 ---
> > > 1 file changed, 3 deletions(-)
> > >
> > > diff --git a/drivers/pci/access.c b/drivers/pci/access.c
> > > index 79c4a2e..b3fc164 100644
> > > --- a/drivers/pci/access.c
> > > +++ b/drivers/pci/access.c
> > > @@ -160,9 +160,6 @@ int pci_generic_config_write32(struct pci_bus *bus,
> > > unsigned int devfn,
> > >* write happen to have any RW1C (write-one-to-clear) bits set, we
> > >* just inadvertently cleared something we shouldn't have.
> > >*/
> > > - dev_warn_ratelimited(>dev, "%d-byte config write to
> > > %04x:%02x:%02x.%d offset %#x may corrupt adjacent RW1C bits\n",
> > > - size, pci_domain_nr(bus), bus->number,
> > > - PCI_SLOT(devfn), PCI_FUNC(devfn), where);
> >
> > We just changed this printk (see [1]), but I think we still have this
> > lockdep problem even after Mark's change. So I guess we need another
> > think about this.
> >
> > Maybe we can print
Re: [PATCH] PCI: Don't use Printk in raw_spinlocks
On 2020-09-10 7:21 a.m., Rob Herring wrote:
> On Wed, Sep 9, 2020 at 8:07 PM Bjorn Helgaas wrote:
>> [+cc Mark, Florian, Rob, Scott]
>>
>> On Sat, Aug 01, 2020 at 09:25:49AM +0800, Xingxing Su wrote:
>>> Do not use printk in raw_spinlocks,
>>> it will cause BUG: Invalid wait context.
>>>
>>> The trace reported by lockdep follows.
>>>
>>> [2.986113] =
>>> [2.986115] [ BUG: Invalid wait context ]
>>> [2.986116] 5.8.0-rc1+ #11 Not tainted
>>> [2.986118] -
>>> [2.986120] swapper/0/1 is trying to lock:
>>> [2.986122] 80f5ddd8 (console_owner){}-{3:3}, at:
>>> console_unlock+0x284/0x820
>>> [2.986130] other info that might help us debug this:
>>> [2.986132] context-{5:5}
>>> [2.986134] 3 locks held by swapper/0/1:
>>> [2.986135] #0: 9807fa03c990 (>mutex){}-{0:0}, at:
>>> device_driver_attach+0x28/0x90
>>> [2.986144] #1: 80fb83a8 (pci_lock){}-{2:2}, at:
>>> pci_bus_write_config_word+0x60/0xb8
>>> [2.986152] #2: 80f5ded0 (console_lock){+.+.}-{0:0}, at:
>>> vprintk_emit+0x1b0/0x3b8
>>> [2.986161] stack backtrace:
>>> [2.986163] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #11
>>> [2.986164] Stack : 1d67 9800030be9b0 0001
>>> 7b2aba74f6c4785b
>>> [2.986172] 7b2aba74f6c4785b 9807f89cb438
>>> 80e7dc80
>>> [2.986181] 0001 000a 0001
>>> 0001
>>> [2.986189] 80f4e156 fffd 80cc2d98
>>> f800
>>> [2.986197] 2400 80f4
>>>
>>> [2.986205] 9500cce0 80f5
>>> 81546318
>>> [2.986213] 81c4c3c0 0018 bc00
>>>
>>> [2.986221] 8134 9807f89c8000 9807f89cb430
>>> 9807f8a0
>>> [2.986229] 806be568
>>>
>>> [2.986237] 80211c1c
>>> 7b2aba74f6c4785b
>>> [2.986245] ...
>>> [2.986250] Call Trace:
>>> [2.986251] [] show_stack+0x9c/0x130
>>> [2.986253] [] dump_stack+0xe8/0x150
>>> [2.986255] [] __lock_acquire+0x570/0x3250
>>> [2.986257] [] lock_acquire+0x118/0x558
>>> [2.986259] [] console_unlock+0x2e4/0x820
>>> [2.986261] [] vprintk_emit+0x1c0/0x3b8
>>> [2.986263] [] dev_vprintk_emit+0x1c8/0x210
>>> [2.986265] [] dev_printk_emit+0x3c/0x60
>>> [2.986267] [] _dev_warn+0x5c/0x80
>>> [2.986269] [] pci_generic_config_write32+0x154/0x160
>>> [2.986271] [] pci_bus_write_config_word+0x84/0xb8
>>> [2.986273] [] pci_setup_device+0x22c/0x768
>>> [2.986275] [] pci_scan_single_device+0xc8/0x100
>>> [2.986277] [] pci_scan_slot+0xb0/0x178
>>> [2.986279] [] pci_scan_child_bus_extend+0x5c/0x370
>>> [2.986281] [] pci_scan_root_bus_bridge+0x6c/0xf0
>>> [2.986283] [] pci_host_probe+0x1c/0xd8
>>> [2.986285] [] platform_drv_probe+0x54/0xb8
>>> [2.986287] [] really_probe+0x130/0x388
>>> [2.986289] [] driver_probe_device+0x64/0xd8
>>> [2.986291] [] device_driver_attach+0x84/0x90
>>> [2.986293] [] __driver_attach+0xc8/0x128
>>> [2.986295] [] bus_for_each_dev+0x74/0xd8
>>> [2.986297] [] bus_add_driver+0x170/0x250
>>> [2.986299] [] driver_register+0x84/0x150
>>> [2.986301] [] do_one_initcall+0x98/0x458
>>> [2.986303] [] kernel_init_freeable+0x2c0/0x36c
>>> [2.986305] [] kernel_init+0x10/0x128
>>> [2.986307] [] ret_from_kernel_thread+0x14/0x1c
>>>
>>> Signed-off-by: Xingxing Su
>>> ---
>>> drivers/pci/access.c | 3 ---
>>> 1 file changed, 3 deletions(-)
>>>
>>> diff --git a/drivers/pci/access.c b/drivers/pci/access.c
>>> index 79c4a2e..b3fc164 100644
>>> --- a/drivers/pci/access.c
>>> +++ b/drivers/pci/access.c
>>> @@ -160,9 +160,6 @@ int pci_generic_config_write32(struct pci_bus *bus,
>>> unsigned int devfn,
>>>* write happen to have any RW1C (write-one-to-clear) bits set, we
>>>* just inadvertently cleared something we shouldn't have.
>>>*/
>>> - dev_warn_ratelimited(>dev, "%d-byte config write to
>>> %04x:%02x:%02x.%d offset %#x may corrupt adjacent RW1C bits\n",
>>> - size, pci_domain_nr(bus), bus->number,
>>> - PCI_SLOT(devfn), PCI_FUNC(devfn), where);
>> We just changed this printk (see [1]), but I think we still have this
>> lockdep problem even after Mark's change. So I guess we need another
>> think about this.
>>
>> Maybe we can print something when registering pci_ops that use
>> pci_generic_config_write32()?
> That was my suggestion, but as Mark pointed out that doesn't work if
> pci_generic_config_write32 is wrapped (which is 4 out of 8 cases).
>
Re: [PATCH] PCI: Don't use Printk in raw_spinlocks
[+cc Mark, Florian, Rob, Scott]
On Sat, Aug 01, 2020 at 09:25:49AM +0800, Xingxing Su wrote:
> Do not use printk in raw_spinlocks,
> it will cause BUG: Invalid wait context.
>
> The trace reported by lockdep follows.
>
> [2.986113] =
> [2.986115] [ BUG: Invalid wait context ]
> [2.986116] 5.8.0-rc1+ #11 Not tainted
> [2.986118] -
> [2.986120] swapper/0/1 is trying to lock:
> [2.986122] 80f5ddd8 (console_owner){}-{3:3}, at:
> console_unlock+0x284/0x820
> [2.986130] other info that might help us debug this:
> [2.986132] context-{5:5}
> [2.986134] 3 locks held by swapper/0/1:
> [2.986135] #0: 9807fa03c990 (>mutex){}-{0:0}, at:
> device_driver_attach+0x28/0x90
> [2.986144] #1: 80fb83a8 (pci_lock){}-{2:2}, at:
> pci_bus_write_config_word+0x60/0xb8
> [2.986152] #2: 80f5ded0 (console_lock){+.+.}-{0:0}, at:
> vprintk_emit+0x1b0/0x3b8
> [2.986161] stack backtrace:
> [2.986163] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #11
> [2.986164] Stack : 1d67 9800030be9b0 0001
> 7b2aba74f6c4785b
> [2.986172] 7b2aba74f6c4785b 9807f89cb438
> 80e7dc80
> [2.986181] 0001 000a 0001
> 0001
> [2.986189] 80f4e156 fffd 80cc2d98
> f800
> [2.986197] 2400 80f4
>
> [2.986205] 9500cce0 80f5
> 81546318
> [2.986213] 81c4c3c0 0018 bc00
>
> [2.986221] 8134 9807f89c8000 9807f89cb430
> 9807f8a0
> [2.986229] 806be568
>
> [2.986237] 80211c1c
> 7b2aba74f6c4785b
> [2.986245] ...
> [2.986250] Call Trace:
> [2.986251] [] show_stack+0x9c/0x130
> [2.986253] [] dump_stack+0xe8/0x150
> [2.986255] [] __lock_acquire+0x570/0x3250
> [2.986257] [] lock_acquire+0x118/0x558
> [2.986259] [] console_unlock+0x2e4/0x820
> [2.986261] [] vprintk_emit+0x1c0/0x3b8
> [2.986263] [] dev_vprintk_emit+0x1c8/0x210
> [2.986265] [] dev_printk_emit+0x3c/0x60
> [2.986267] [] _dev_warn+0x5c/0x80
> [2.986269] [] pci_generic_config_write32+0x154/0x160
> [2.986271] [] pci_bus_write_config_word+0x84/0xb8
> [2.986273] [] pci_setup_device+0x22c/0x768
> [2.986275] [] pci_scan_single_device+0xc8/0x100
> [2.986277] [] pci_scan_slot+0xb0/0x178
> [2.986279] [] pci_scan_child_bus_extend+0x5c/0x370
> [2.986281] [] pci_scan_root_bus_bridge+0x6c/0xf0
> [2.986283] [] pci_host_probe+0x1c/0xd8
> [2.986285] [] platform_drv_probe+0x54/0xb8
> [2.986287] [] really_probe+0x130/0x388
> [2.986289] [] driver_probe_device+0x64/0xd8
> [2.986291] [] device_driver_attach+0x84/0x90
> [2.986293] [] __driver_attach+0xc8/0x128
> [2.986295] [] bus_for_each_dev+0x74/0xd8
> [2.986297] [] bus_add_driver+0x170/0x250
> [2.986299] [] driver_register+0x84/0x150
> [2.986301] [] do_one_initcall+0x98/0x458
> [2.986303] [] kernel_init_freeable+0x2c0/0x36c
> [2.986305] [] kernel_init+0x10/0x128
> [2.986307] [] ret_from_kernel_thread+0x14/0x1c
>
> Signed-off-by: Xingxing Su
> ---
> drivers/pci/access.c | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff --git a/drivers/pci/access.c b/drivers/pci/access.c
> index 79c4a2e..b3fc164 100644
> --- a/drivers/pci/access.c
> +++ b/drivers/pci/access.c
> @@ -160,9 +160,6 @@ int pci_generic_config_write32(struct pci_bus *bus,
> unsigned int devfn,
>* write happen to have any RW1C (write-one-to-clear) bits set, we
>* just inadvertently cleared something we shouldn't have.
>*/
> - dev_warn_ratelimited(>dev, "%d-byte config write to
> %04x:%02x:%02x.%d offset %#x may corrupt adjacent RW1C bits\n",
> - size, pci_domain_nr(bus), bus->number,
> - PCI_SLOT(devfn), PCI_FUNC(devfn), where);
We just changed this printk (see [1]), but I think we still have this
lockdep problem even after Mark's change. So I guess we need another
think about this.
Maybe we can print something when registering pci_ops that use
pci_generic_config_write32()?
[1]
https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/commit/?h=pci/enumeration=92ff4b49c2a9
> mask = ~(((1 << (size * 8)) - 1) << ((where & 0x3) * 8));
> tmp = readl(addr) & mask;
> --
> 2.1.0
>
[PATCH] PCI: Don't use Printk in raw_spinlocks
Do not use printk in raw_spinlocks,
it will cause BUG: Invalid wait context.
The trace reported by lockdep follows.
[2.986113] =
[2.986115] [ BUG: Invalid wait context ]
[2.986116] 5.8.0-rc1+ #11 Not tainted
[2.986118] -
[2.986120] swapper/0/1 is trying to lock:
[2.986122] 80f5ddd8 (console_owner){}-{3:3}, at:
console_unlock+0x284/0x820
[2.986130] other info that might help us debug this:
[2.986132] context-{5:5}
[2.986134] 3 locks held by swapper/0/1:
[2.986135] #0: 9807fa03c990 (>mutex){}-{0:0}, at:
device_driver_attach+0x28/0x90
[2.986144] #1: 80fb83a8 (pci_lock){}-{2:2}, at:
pci_bus_write_config_word+0x60/0xb8
[2.986152] #2: 80f5ded0 (console_lock){+.+.}-{0:0}, at:
vprintk_emit+0x1b0/0x3b8
[2.986161] stack backtrace:
[2.986163] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #11
[2.986164] Stack : 1d67 9800030be9b0 0001
7b2aba74f6c4785b
[2.986172] 7b2aba74f6c4785b 9807f89cb438
80e7dc80
[2.986181] 0001 000a 0001
0001
[2.986189] 80f4e156 fffd 80cc2d98
f800
[2.986197] 2400 80f4
[2.986205] 9500cce0 80f5
81546318
[2.986213] 81c4c3c0 0018 bc00
[2.986221] 8134 9807f89c8000 9807f89cb430
9807f8a0
[2.986229] 806be568
[2.986237] 80211c1c
7b2aba74f6c4785b
[2.986245] ...
[2.986250] Call Trace:
[2.986251] [] show_stack+0x9c/0x130
[2.986253] [] dump_stack+0xe8/0x150
[2.986255] [] __lock_acquire+0x570/0x3250
[2.986257] [] lock_acquire+0x118/0x558
[2.986259] [] console_unlock+0x2e4/0x820
[2.986261] [] vprintk_emit+0x1c0/0x3b8
[2.986263] [] dev_vprintk_emit+0x1c8/0x210
[2.986265] [] dev_printk_emit+0x3c/0x60
[2.986267] [] _dev_warn+0x5c/0x80
[2.986269] [] pci_generic_config_write32+0x154/0x160
[2.986271] [] pci_bus_write_config_word+0x84/0xb8
[2.986273] [] pci_setup_device+0x22c/0x768
[2.986275] [] pci_scan_single_device+0xc8/0x100
[2.986277] [] pci_scan_slot+0xb0/0x178
[2.986279] [] pci_scan_child_bus_extend+0x5c/0x370
[2.986281] [] pci_scan_root_bus_bridge+0x6c/0xf0
[2.986283] [] pci_host_probe+0x1c/0xd8
[2.986285] [] platform_drv_probe+0x54/0xb8
[2.986287] [] really_probe+0x130/0x388
[2.986289] [] driver_probe_device+0x64/0xd8
[2.986291] [] device_driver_attach+0x84/0x90
[2.986293] [] __driver_attach+0xc8/0x128
[2.986295] [] bus_for_each_dev+0x74/0xd8
[2.986297] [] bus_add_driver+0x170/0x250
[2.986299] [] driver_register+0x84/0x150
[2.986301] [] do_one_initcall+0x98/0x458
[2.986303] [] kernel_init_freeable+0x2c0/0x36c
[2.986305] [] kernel_init+0x10/0x128
[2.986307] [] ret_from_kernel_thread+0x14/0x1c
Signed-off-by: Xingxing Su
---
drivers/pci/access.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 79c4a2e..b3fc164 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -160,9 +160,6 @@ int pci_generic_config_write32(struct pci_bus *bus,
unsigned int devfn,
* write happen to have any RW1C (write-one-to-clear) bits set, we
* just inadvertently cleared something we shouldn't have.
*/
- dev_warn_ratelimited(>dev, "%d-byte config write to
%04x:%02x:%02x.%d offset %#x may corrupt adjacent RW1C bits\n",
-size, pci_domain_nr(bus), bus->number,
-PCI_SLOT(devfn), PCI_FUNC(devfn), where);
mask = ~(((1 << (size * 8)) - 1) << ((where & 0x3) * 8));
tmp = readl(addr) & mask;
--
2.1.0
