On Thu, Mar 20, 2014 at 4:03 AM, Zhang, Rui <rui.zhang@xxxxxxxxx> wrote: > > >> -----Original Message----- >> From: Lu, Aaron >> Sent: Thursday, March 20, 2014 10:24 AM >> To: Rafael J. Wysocki; Borislav Petkov >> Cc: lkml; x86@xxxxxxxxxx; 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. > 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] [<ffffffff816112e3>] dump_stack+0x4f/0x7c >> >> [ 0.493420] [<ffffffff8104e9bc>] warn_slowpath_common+0x8c/0xc0 >> >> [ 0.493503] [<ffffffff8104eaa6>] warn_slowpath_fmt+0x46/0x50 >> >> [ 0.493588] [<ffffffff8103f1e2>] __ioremap_caller+0x372/0x380 >> >> [ 0.493674] [<ffffffff810211a2>] ? >> snb_uncore_imc_init_box+0x62/0x90 >> >> [ 0.493761] [<ffffffff8103f247>] ioremap_nocache+0x17/0x20 >> >> [ 0.493846] [<ffffffff810211a2>] >> snb_uncore_imc_init_box+0x62/0x90 >> >> [ 0.493933] [<ffffffff81022925>] uncore_pci_probe+0xe5/0x1e0 >> >> [ 0.494020] [<ffffffff812d487e>] local_pci_probe+0x4e/0xa0 >> >> [ 0.494104] [<ffffffff81418a59>] ? get_device+0x19/0x20 >> >> [ 0.494213] [<ffffffff812d5cd1>] pci_device_probe+0xe1/0x130 >> >> [ 0.494300] [<ffffffff8141d3cb>] driver_probe_device+0x7b/0x240 >> >> [ 0.494385] [<ffffffff8141d63b>] __driver_attach+0xab/0xb0 >> >> [ 0.494469] [<ffffffff8141d590>] ? >> driver_probe_device+0x240/0x240 >> >> [ 0.494551] [<ffffffff8141b71e>] bus_for_each_dev+0x5e/0x90 >> >> [ 0.494634] [<ffffffff8141cede>] driver_attach+0x1e/0x20 >> >> [ 0.494718] [<ffffffff8141ca57>] bus_add_driver+0x117/0x230 >> >> [ 0.494802] [<ffffffff8141dd34>] driver_register+0x64/0xf0 >> >> [ 0.494884] [<ffffffff812d4c14>] __pci_register_driver+0x64/0x70 >> >> [ 0.494972] [<ffffffff81d0319b>] ? uncore_types_init+0x19c/0x19c >> >> [ 0.495056] [<ffffffff81d03312>] intel_uncore_init+0x177/0x41c >> >> [ 0.495155] [<ffffffff81d0319b>] ? uncore_types_init+0x19c/0x19c >> >> [ 0.495242] [<ffffffff8100029e>] do_one_initcall+0x4e/0x170 >> >> [ 0.495326] [<ffffffff81071100>] ? parse_args+0x60/0x360 >> >> [ 0.495411] [<ffffffff81cfbfb8>] >> kernel_init_freeable+0x106/0x19a >> >> [ 0.495497] [<ffffffff81cfb83b>] ? do_early_param+0x86/0x86 >> >> [ 0.495582] [<ffffffff81607ef0>] ? rest_init+0xd0/0xd0 >> >> [ 0.495666] [<ffffffff81607efe>] kernel_init+0xe/0xf0 >> >> [ 0.495749] [<ffffffff81621f6c>] ret_from_fork+0x7c/0xb0 >> >> [ 0.495831] [<ffffffff81607ef0>] ? 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 >> >> ... >> >> >> >> >> > > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
