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0a72761b27
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXygcLwAKCRCRxhvAZXjc ohajAP4n5E3BmN0jpIviXT4eNhP62jzxJtxlVXtgGT3D8b1mpQEA5n8NSOlQLoAh yUGsjtwR9xDcHMcrhXD3yN6eYJSK0A8= =tn4R -----END PGP SIGNATURE----- Merge tag 'threads-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull thread updates from Christian Brauner: "This contains the changes to add the missing support for attaching to time namespaces via pidfds. Last cycle setns() was changed to support attaching to multiple namespaces atomically. This requires all namespaces to have a point of no return where they can't fail anymore. Specifically, <namespace-type>_install() is allowed to perform permission checks and install the namespace into the new struct nsset that it has been given but it is not allowed to make visible changes to the affected task. Once <namespace-type>_install() returns, anything that the given namespace type additionally requires to be setup needs to ideally be done in a function that can't fail or if it fails the failure must be non-fatal. For time namespaces the relevant functions that fell into this category were timens_set_vvar_page() and vdso_join_timens(). The latter could still fail although it didn't need to. This function is only implemented for vdso_join_timens() in current mainline. As discussed on-list (cf. [1]), in order to make setns() support time namespaces when attaching to multiple namespaces at once properly we changed vdso_join_timens() to always succeed. So vdso_join_timens() replaces the mmap_write_lock_killable() with mmap_read_lock(). Please note that arm is about to grow vdso support for time namespaces (possibly this merge window). We've synced on this change and arm64 also uses mmap_read_lock(), i.e. makes vdso_join_timens() a function that can't fail. Once the changes here and the arm64 changes have landed, vdso_join_timens() should be turned into a void function so it's obvious to callers and implementers on other architectures that the expectation is that it can't fail. We didn't do this right away because it would've introduced unnecessary merge conflicts between the two trees for no major gain. As always, tests included" [1]: https://lore.kernel.org/lkml/20200611110221.pgd3r5qkjrjmfqa2@wittgenstein * tag 'threads-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: tests: add CLONE_NEWTIME setns tests nsproxy: support CLONE_NEWTIME with setns() timens: add timens_commit() helper timens: make vdso_join_timens() always succeed |
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| boot | ||
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| crypto | ||
| entry | ||
| events | ||
| hyperv | ||
| ia32 | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| pci | ||
| platform | ||
| power | ||
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| ras | ||
| realmode | ||
| tools | ||
| um | ||
| video | ||
| xen | ||
| .gitignore | ||
| Kbuild | ||
| Kconfig | ||
| Kconfig.assembler | ||
| Kconfig.cpu | ||
| Kconfig.debug | ||
| Makefile | ||
| Makefile.um | ||
| Makefile_32.cpu | ||