diff options
author | Rui Wang <rui.y.wang@intel.com> | 2016-08-17 16:00:36 +0800 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-08-18 11:45:18 +0200 |
commit | 162b83bd5f1d7124e21da78bcf2685b9824d9ef0 (patch) | |
tree | 780ea3f1c6871f50afd0cc2905e99da55248aac3 /drivers/acpi | |
parent | 6ab7eba5db93c11d61f6f7fbe21edbc875b26c1a (diff) | |
download | linux-162b83bd5f1d7124e21da78bcf2685b9824d9ef0.tar.bz2 |
x86/ioapic: Fix lost IOAPIC resource after hot-removal and hotadd
IOAPIC resource at 0xfecxxxxx gets lost from /proc/iomem after
hot-removing and then hot-adding the IOAPIC device.
After system boot, in /proc/iomem:
fec00000-fecfffff : PNP0003:00
fec00000-fec003ff : IOAPIC 0
fec01000-fec013ff : IOAPIC 1
fec40000-fec403ff : IOAPIC 2
fec80000-fec803ff : IOAPIC 3
fecc0000-fecc03ff : IOAPIC 4
Then hot-remove IOAPIC 2 and hot-add it again:
fec00000-fecfffff : PNP0003:00
fec00000-fec003ff : IOAPIC 0
fec01000-fec013ff : IOAPIC 1
fec80000-fec803ff : IOAPIC 3
fecc0000-fecc03ff : IOAPIC 4
The range at 0xfec40000 is lost from /proc/iomem - which is a bug.
This bug happens because handle_ioapic_add() requests resources from
either PCI config BAR or ACPI "_CRS", not both. But Intel platforms
map the IOxAPIC registers both at the PCI config BAR (called MBAR, dynamic),
and at the ACPI "_CRS" (called ABAR, static). The 0xfecX_YZ00 to 0xfecX_YZFF
range appears in "_CRS" of each IOAPIC device.
Both ranges should be claimed from /proc/iomem for exclusive use.
Signed-off-by: Rui Wang <rui.y.wang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bhelgaas@google.com
Cc: helgaas@kernel.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: rjw@rjwysocki.net
Cc: tony.luck@intel.com
Link: http://lkml.kernel.org/r/1471420837-31003-5-git-send-email-rui.y.wang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/acpi')
-rw-r--r-- | drivers/acpi/ioapic.c | 36 |
1 files changed, 20 insertions, 16 deletions
diff --git a/drivers/acpi/ioapic.c b/drivers/acpi/ioapic.c index 8ab6d426c178..ee201111e063 100644 --- a/drivers/acpi/ioapic.c +++ b/drivers/acpi/ioapic.c @@ -97,7 +97,7 @@ static acpi_status handle_ioapic_add(acpi_handle handle, u32 lvl, unsigned long long gsi_base; struct acpi_pci_ioapic *ioapic; struct pci_dev *dev = NULL; - struct resource *res = NULL; + struct resource *res = NULL, *pci_res = NULL, *crs_res; char *type = NULL; if (!acpi_is_ioapic(handle, &type)) @@ -137,23 +137,28 @@ static acpi_status handle_ioapic_add(acpi_handle handle, u32 lvl, pci_set_master(dev); if (pci_request_region(dev, 0, type)) goto exit_disable; - res = &dev->resource[0]; + pci_res = &dev->resource[0]; ioapic->pdev = dev; } else { pci_dev_put(dev); dev = NULL; + } - res = &ioapic->res; - acpi_walk_resources(handle, METHOD_NAME__CRS, setup_res, res); - if (res->flags == 0) { - acpi_handle_warn(handle, "failed to get resource\n"); - goto exit_free; - } else if (request_resource(&iomem_resource, res)) { - acpi_handle_warn(handle, "failed to insert resource\n"); - goto exit_free; - } + crs_res = &ioapic->res; + acpi_walk_resources(handle, METHOD_NAME__CRS, setup_res, crs_res); + if (crs_res->flags == 0) { + acpi_handle_warn(handle, "failed to get resource\n"); + goto exit_release; + } else if (request_resource(&iomem_resource, crs_res)) { + acpi_handle_warn(handle, "failed to insert resource\n"); + goto exit_release; } + /* try pci resource first, then "_CRS" resource */ + res = pci_res; + if (!res || !res->flags) + res = crs_res; + if (acpi_register_ioapic(handle, res->start, (u32)gsi_base)) { acpi_handle_warn(handle, "failed to register IOAPIC\n"); goto exit_release; @@ -174,14 +179,13 @@ done: exit_release: if (dev) pci_release_region(dev, 0); - else - release_resource(res); + if (ioapic->res.flags && ioapic->res.parent) + release_resource(&ioapic->res); exit_disable: if (dev) pci_disable_device(dev); exit_put: pci_dev_put(dev); -exit_free: kfree(ioapic); exit: mutex_unlock(&ioapic_list_lock); @@ -217,9 +221,9 @@ int acpi_ioapic_remove(struct acpi_pci_root *root) pci_release_region(ioapic->pdev, 0); pci_disable_device(ioapic->pdev); pci_dev_put(ioapic->pdev); - } else if (ioapic->res.flags && ioapic->res.parent) { - release_resource(&ioapic->res); } + if (ioapic->res.flags && ioapic->res.parent) + release_resource(&ioapic->res); list_del(&ioapic->list); kfree(ioapic); } |