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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-05 11:59:05 -0700
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Merge tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-coregrafted
Pull driver core fixes from Danilo Krummrich: - Fix kernfs listxattr() not returning security xattr names (e.g. SELinux labels) when the kernfs node has no allocated kernfs_iattrs - Fix silent truncation of IRQ vector indices in the Rust PCI abstractions - Don't select OF from DRIVER_PE_KUNIT_TEST; skip the test when OF is disabled instead of silently enabling extra kernel functionality - Russ Weight is retiring from kernel development; update the Firmware Loader sysfs contact to the driver-core mailing list, add a CREDITS entry for Firmware Upload, and update MAINTAINERS accordingly * tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: MAINTAINERS: Remove Russ Weight from Firmware Loader CREDITS: Add CREDITS entry for Firmware Upload firmware_loader: Change contact for sysfs nodes rust: pci: reject IRQ vector indices that do not fit in u32 kernfs: preserve security xattrs without allocating iattrs drivers: base: test: DRIVER_PE_KUNIT_TEST should not select OF
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+==========================
+ELF Note PowerPC Namespace
+==========================
+
+The PowerPC namespace in an ELF Note of the kernel binary is used to store
+capabilities and information which can be used by a bootloader or userland.
+
+Types and Descriptors
+---------------------
+
+The types to be used with the "PowerPC" namespace are defined in [#f1]_.
+
+ 1) PPC_ELFNOTE_CAPABILITIES
+
+Define the capabilities supported/required by the kernel. This type uses a
+bitmap as "descriptor" field. Each bit is described below:
+
+- Ultravisor-capable bit (PowerNV only).
+
+.. code-block:: c
+
+ #define PPCCAP_ULTRAVISOR_BIT (1 << 0)
+
+Indicate that the powerpc kernel binary knows how to run in an
+ultravisor-enabled system.
+
+In an ultravisor-enabled system, some machine resources are now controlled
+by the ultravisor. If the kernel is not ultravisor-capable, but it ends up
+being run on a machine with ultravisor, the kernel will probably crash
+trying to access ultravisor resources. For instance, it may crash in early
+boot trying to set the partition table entry 0.
+
+In an ultravisor-enabled system, a bootloader could warn the user or prevent
+the kernel from being run if the PowerPC ultravisor capability doesn't exist
+or the Ultravisor-capable bit is not set.
+
+References
+----------
+
+.. [#f1] arch/powerpc/include/asm/elfnote.h
+