> -----Original Message----- > From: Stephane Eranian [mailto:eranian@google.com] > Sent: Thursday, March 20, 2014 11:35 AM > To: Zhang, Rui > Cc: Lu, Aaron; Rafael J. Wysocki; Borislav Petkov; lkml; x86@kernel.org; > Bjorn Helgaas; Linux PCI; ACPI Devel Maling List; Yinghai Lu; H. Peter > Anvin; Yan, Zheng Z > Subject: Re: Info: mapping multiple BARs. Your kernel is fine. > Importance: High > > On Thu, Mar 20, 2014 at 4:03 AM, Zhang, Rui wrote: > > > > > >> -----Original Message----- > >> From: Lu, Aaron > >> Sent: Thursday, March 20, 2014 10:24 AM > >> To: Rafael J. Wysocki; Borislav Petkov > >> Cc: lkml; x86@kernel.org; Bjorn Helgaas; Linux PCI; ACPI Devel > Maling > >> List; Zhang, Rui; Yinghai Lu; H. Peter Anvin; Stephane Eranian > >> Subject: Re: Info: mapping multiple BARs. Your kernel is fine. > >> Importance: High > >> > >> On 03/15/2014 10:15 PM, Rafael J. Wysocki wrote: > >> > [CC list rearranged] > >> > > >> > On Monday, February 24, 2014 05:24:00 PM Borislav Petkov wrote: > >> >> This started happening this morning after booting -rc4+tip, let's > >> add > >> >> *everybody* to CC :-) > >> >> > >> >> We have intel_uncore_init, snb_uncore_imc_init_box, > >> >> uncore_pci_probe and other goodies on the stack. > >> > > >> > I've just gone throught this. > >> > > >> > So the problem is that we have the PNP "system" driver whose only > >> > purpose seems to be to reserve system resources so that the PCI > >> > layer doesn't assign them to new devices on hotplug (disclaimer: I > >> > didn't invent it, I only read the code and comments in there). > >> > >> And to PCI devices which have uninitialized BARs. > >> > >> > > >> > It does that for ACPI device objects having the "PNP0C02" and > >> "PNP0C01" IDs. > >> > > >> > Apparently, snb_uncore_imc_init_box() steps on a range already > >> > reserved by that driver on your box. And this doesn't seem to be > a > >> > coincidence, because the ACPI device object in question probably > >> > *does* correspond to the memory controller that the uncore driver > >> attempts to use. > >> > > >> > I'm not sure how to address that right now to be honest. Arguably, > >> > the PNP "system" driver should be replaced with something saner, > >> > but still the resources it claims need to be kept out of reach of > >> > the PCI's resource allocation code. > >> > >> The quirk_system_pci_resources is meant to disable PNP devices' > >> resource if they collide with any known PCI device's BAR. I'm not > >> sure why it doesn't work here, perhaps the uncore PCI device doesn't > >> have a BAR that falls in the PNP device's resource window? > >> > > I've talked with Yan Zheng, and I was told that this resource > "0xfed10000 - 0xfed15fff" > > is got from PCI device register directly, which is not in its BAR > range. > > Thus IMO, it is impossible for PNP layer to be aware of this resource. > > > That is not what the perf_event code does. Nothing is hardcoded except > the IMC PCI device ids. The BAR offset is hardcoded that's all. The > 0xfed10000 is discovered. > The resource length is also hardcoded to 0x6000, right? This is probably a problem, because only if the resource length read from PCI config space is larger than 0x4000, drivers/pnp/quirks.c will detect the conflict and disable the PNP0C02 resource 0xfed10000 - 0xfed13fff, and the PCI device can request this resource successfully. In order to check this, can you please attach the dmesg output after boot? Thanks, rui > > BTW, about drivers/pnp/system.c, if its ONLY purpose is to prevent > > those resources from being allocated to uninitialized PCI devices, > > then IMO, the best way to do this is make PCI bus handle those > > PNP0C01/PNP0C02 resources directly, probably via a platform callback, > > say, 1. make drivers/pnp/system.c a no-op for PNPACPI, by checking > pnp_dev->protocol. > > 2. introduce acpi_check_reserved_resource() to parsing > PNP0C01/PNP0C02 resources. > > 3. in PCI bus, invoke acpi_check_reserved_resource() when assigning > > resources to PCI devices. > > > > Thanks, > > rui > > > >> Thanks, > >> Aaron > >> > >> > > >> >> ... > >> >> [ 0.488998] software IO TLB [mem 0xcac30000-0xcec30000] (64MB) > >> mapped at [ffff8800cac30000-ffff8800cec2ffff] > >> >> [ 0.489975] resource map sanity check conflict: 0xfed10000 > >> 0xfed15fff 0xfed10000 0xfed13fff pnp 00:01 > >> >> [ 0.490079] ------------[ cut here ]------------ > >> >> [ 0.490204] WARNING: CPU: 2 PID: 1 at > arch/x86/mm/ioremap.c:171 > >> __ioremap_caller+0x372/0x380() > >> >> [ 0.490306] Info: mapping multiple BARs. Your kernel is fine. > >> >> [ 0.490371] Modules linked in: > >> >> [ 0.490558] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 3.14.0- > rc4+ > >> #1 > >> >> [ 0.490642] Hardware name: LENOVO 2320CTO/2320CTO, BIOS > G2ET86WW > >> (2.06 ) 11/13/2012 > >> >> [ 0.490742] 00000000000000ab ffff880213d01ad8 > ffffffff816112e3 > >> 0000000000000006 > >> >> [ 0.491032] ffff880213d01b28 ffff880213d01b18 > ffffffff8104e9bc > >> ffff880213d01b08 > >> >> [ 0.491343] ffffc90000c58000 00000000fed10000 > 00000000fed10000 > >> 0000000000006000 > >> >> [ 0.491631] Call Trace: > >> >> [ 0.493337] [] dump_stack+0x4f/0x7c > >> >> [ 0.493420] [] > warn_slowpath_common+0x8c/0xc0 > >> >> [ 0.493503] [] warn_slowpath_fmt+0x46/0x50 > >> >> [ 0.493588] [] __ioremap_caller+0x372/0x380 > >> >> [ 0.493674] [] ? > >> snb_uncore_imc_init_box+0x62/0x90 > >> >> [ 0.493761] [] ioremap_nocache+0x17/0x20 > >> >> [ 0.493846] [] > >> snb_uncore_imc_init_box+0x62/0x90 > >> >> [ 0.493933] [] uncore_pci_probe+0xe5/0x1e0 > >> >> [ 0.494020] [] local_pci_probe+0x4e/0xa0 > >> >> [ 0.494104] [] ? get_device+0x19/0x20 > >> >> [ 0.494213] [] pci_device_probe+0xe1/0x130 > >> >> [ 0.494300] [] > driver_probe_device+0x7b/0x240 > >> >> [ 0.494385] [] __driver_attach+0xab/0xb0 > >> >> [ 0.494469] [] ? > >> driver_probe_device+0x240/0x240 > >> >> [ 0.494551] [] bus_for_each_dev+0x5e/0x90 > >> >> [ 0.494634] [] driver_attach+0x1e/0x20 > >> >> [ 0.494718] [] bus_add_driver+0x117/0x230 > >> >> [ 0.494802] [] driver_register+0x64/0xf0 > >> >> [ 0.494884] [] > __pci_register_driver+0x64/0x70 > >> >> [ 0.494972] [] ? > uncore_types_init+0x19c/0x19c > >> >> [ 0.495056] [] > intel_uncore_init+0x177/0x41c > >> >> [ 0.495155] [] ? > uncore_types_init+0x19c/0x19c > >> >> [ 0.495242] [] do_one_initcall+0x4e/0x170 > >> >> [ 0.495326] [] ? parse_args+0x60/0x360 > >> >> [ 0.495411] [] > >> kernel_init_freeable+0x106/0x19a > >> >> [ 0.495497] [] ? do_early_param+0x86/0x86 > >> >> [ 0.495582] [] ? rest_init+0xd0/0xd0 > >> >> [ 0.495666] [] kernel_init+0xe/0xf0 > >> >> [ 0.495749] [] ret_from_fork+0x7c/0xb0 > >> >> [ 0.495831] [] ? rest_init+0xd0/0xd0 > >> >> [ 0.495921] ---[ end trace 428f365c054d9a01 ]--- > >> >> [ 0.496196] RAPL PMU detected, hw unit 2^-16 Joules, API unit > is > >> 2^-32 Joules, 3 fixed counters 163840 ms ovfl timer > >> >> [ 0.498598] futex hash table entries: 1024 (order: 5, 131072 > >> bytes) > >> >> [ 0.498833] audit: initializing netlink subsys (disabled) > >> >> [ 0.499024] audit: type=2000 audit(1393259866.477:1): > initialized > >> >> ... > >> >> > >> >> > >> > > >