linux-dev/arch/powerpc/kernel/security.c, branch linus/master

powerpc: add link stack flush mitigation status in debugfs.

2022-01-31T02:45:23Z

The link stack flush status is not visible in debugfs. It can be enabled even when count cache flush is disabled. Add separate file for its status. Signed-off-by: Michal Suchanek [mpe: Update for change to link_stack_flush_type] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191127220959.6208-1-msuchanek@suse.de

powerpc/kernel: Add __init attribute to eligible functions

2021-12-23T11:33:10Z

Some functions defined in `arch/powerpc/kernel` (and one in `arch/powerpc/ kexec`) are deserving of an `__init` macro attribute. These functions are only called by other initialization functions and therefore should inherit the attribute. Also, change function declarations in header files to include `__init`. Signed-off-by: Nick Child Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211216220035.605465-2-nick.child@ibm.com

powerpc/security: Add a helper to query stf_barrier type

2021-10-07T08:52:58Z

Add a helper to return the stf_barrier type for the current processor. Signed-off-by: Naveen N. Rao Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/3bd5d7f96ea1547991ac2ce3137dc2b220bae285.1633464148.git.naveen.n.rao@linux.vnet.ibm.com

powerpc: rename powerpc_debugfs_root to arch_debugfs_dir

2021-08-13T12:04:26Z

No functional change in this patch. arch_debugfs_dir is the generic kernel name declared in linux/debugfs.h for arch-specific debugfs directory. Architectures like x86/s390 already use the name. Rename powerpc specific powerpc_debugfs_root to arch_debugfs_dir. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210812132831.233794-2-aneesh.kumar@linux.ibm.com

powerpc/security: Add a security feature for STF barrier

2021-06-21T11:13:19Z

Rather than tying this mitigation to RFI L1D flush requirement, add a new bit for it. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210503130243.891868-3-npiggin@gmail.com

Merge branch 'topic/ppc-kvm' into next

2021-06-17T06:51:38Z

Merge some powerpc KVM patches from our topic branch. In particular this brings in Nick's big series rewriting parts of the guest entry/exit path in C. Conflicts: arch/powerpc/kernel/security.c arch/powerpc/kvm/book3s_hv_rmhandlers.S

powerpc/security: Use PPC_RAW_BLR() and PPC_RAW_NOP()

2021-06-15T14:16:48Z

On the road to remove all use of PPC_INST_xxx, replace PPC_INST_BLR by PPC_RAW_BLR(). Same for PPC_INST_NOP. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/c04f88d0e53d2122fbbe92226892a01ebc668b6a.1621506159.git.christophe.leroy@csgroup.eu

KVM: PPC: Book3S HV P9: Implement the rest of the P9 path in C

2021-06-10T12:12:13Z

Almost all logic is moved to C, by introducing a new in_guest mode for the P9 path that branches very early in the KVM interrupt handler to P9 exit code. The main P9 entry and exit assembly is now only about 160 lines of low level stack setup and register save/restore, plus a bad-interrupt handler. There are two motivations for this, the first is just make the code more maintainable being in C. The second is to reduce the amount of code running in a special KVM mode, "realmode". In quotes because with radix it is no longer necessarily real-mode in the MMU, but it still has to be treated specially because it may be in real-mode, and has various important registers like PID, DEC, TB, etc set to guest. This is hostile to the rest of Linux and can't use arbitrary kernel functionality or be instrumented well. This initial patch is a reasonably faithful conversion of the asm code, but it does lack any loop to return quickly back into the guest without switching out of realmode in the case of unimportant or easily handled interrupts. As explained in previous changes, handling HV interrupts very quickly in this low level realmode is not so important for P9 performance, and are important to avoid for security, observability, debugability reasons. Signed-off-by: Nicholas Piggin Reviewed-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210528090752.3542186-15-npiggin@gmail.com

powerpc/security: Make symbol 'stf_barrier' static

2021-04-14T13:04:13Z

The sparse tool complains as follows: arch/powerpc/kernel/security.c:253:6: warning: symbol 'stf_barrier' was not declared. Should it be static? This symbol is not used outside of security.c, so this commit marks it static. Signed-off-by: Li Huafei Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210408033951.28369-1-lihuafei1@huawei.com

powerpc/64: Move security code into security.c

2021-04-08T11:17:43Z

When the original spectre/meltdown mitigations were merged we put them in setup_64.c for lack of a better place. Since then we created security.c for some of the other mitigation related code. But it should all be in there. This sort of code movement can cause trouble for backports, but hopefully this code is relatively stable these days (famous last words). Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210326101201.1973552-1-mpe@ellerman.id.au