mirror of https://gitee.com/openkylin/linux.git
51ef3a004b
PCI core handles save and restore of device state around reset, but when using pci_set_power_state() we can unintentionally trigger a soft reset of the device, where PCI core only restores the BAR state. If we're using vfio-pci's idle D3 support to try to put devices into low power when unused, this might trigger a reset when the device is woken for use. Also power state management by the user, or within a guest, can put the device into D3 power state with potentially limited ability to restore the device if it should undergo a reset. The PCI spec does not define the extent of a soft reset and many devices reporting soft reset on D3->D0 transition do not undergo a PCI config space reset. It's therefore assumed safe to unconditionally restore the remainder of the state if the device indicates soft reset support, even on a user initiated wakeup. Implement a wrapper in vfio-pci to tag devices reporting PM reset support, save their state on transitions into D3 and restore on transitions back to D0. Reported-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> |
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Documentation | ||
LICENSES | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
README
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.