kernel.git/arch/powerpc/kernel/machine_kexec_64.c, branch linux-5.3.y

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230

2019-06-19T15:09:06Z

Based on 2 normalized pattern(s): this source code is licensed under the gnu general public license version 2 see the file copying for more details this source code is licensed under general public license version 2 see extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 52 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Allison Randal Reviewed-by: Alexios Zavras Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.449021192@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc: Activate CONFIG_THREAD_INFO_IN_TASK

2019-02-23T11:31:40Z

This patch activates CONFIG_THREAD_INFO_IN_TASK which moves the thread_info into task_struct. Moving thread_info into task_struct has the following advantages: - It protects thread_info from corruption in the case of stack overflows. - Its address is harder to determine if stack addresses are leaked, making a number of attacks more difficult. This has the following consequences: - thread_info is now located at the beginning of task_struct. - The 'cpu' field is now in task_struct, and only exists when CONFIG_SMP is active. - thread_info doesn't have anymore the 'task' field. This patch: - Removes all recopy of thread_info struct when the stack changes. - Changes the CURRENT_THREAD_INFO() macro to point to current. - Selects CONFIG_THREAD_INFO_IN_TASK. - Modifies raw_smp_processor_id() to get ->cpu from current without including linux/sched.h to avoid circular inclusion and without including asm/asm-offsets.h to avoid symbol names duplication between ASM constants and C constants. - Modifies klp_init_thread_info() to take a task_struct pointer argument. Signed-off-by: Christophe Leroy Reviewed-by: Nicholas Piggin [mpe: Add task_stack.h to livepatch.h to fix build fails] Signed-off-by: Michael Ellerman

powerpc/64/kexec: fix race in kexec when XIVE is shutdown

2018-05-10T13:25:08Z

The kexec_state KEXEC_STATE_IRQS_OFF barrier is reached by all secondary CPUs before the kexec_cpu_down() operation is called on secondaries. This can raise conflicts and provoque errors in the XIVE hcalls when XIVE is shutdown with H_INT_RESET on the primary CPU. To synchronize the kexec_cpu_down() operations and make sure the secondaries have completed their task before the primary starts doing the same, let's move the primary kexec_cpu_down() after the KEXEC_STATE_REAL_MODE barrier. This change of the ending sequence of kexec is mostly useful on the pseries platform but it impacts also the powernv, ps3 and 85xx platforms. powernv can be easily tested and fixed but some caution is required for the other two. Signed-off-by: Cédric Le Goater Signed-off-by: Michael Ellerman

powerpc/64s: Allocate LPPACAs individually

2018-03-30T12:34:24Z

We no longer allocate lppacas in an array, so this patch removes the 1kB static alignment for the structure, and enforces the PAPR alignment requirements at allocation time. We can not reduce the 1kB allocation size however, due to existing KVM hypervisors. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/64: Use array of paca pointers and allocate pacas individually

2018-03-30T12:34:23Z

Change the paca array into an array of pointers to pacas. Allocate pacas individually. This allows flexibility in where the PACAs are allocated. Future work will allocate them node-local. Platforms that don't have address limits on PACAs would be able to defer PACA allocations until later in boot rather than allocate all possible ones up-front then freeing unused. This is slightly more overhead (one additional indirection) for cross CPU paca references, but those aren't too common. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64

2017-11-06T05:48:14Z

CONFIG_PPC_STD_MMU_64 indicates support for the "standard" powerpc MMU on 64-bit CPUs. The "standard" MMU refers to the hash page table MMU found in "server" processors, from IBM mainly. Currently CONFIG_PPC_STD_MMU_64 is == CONFIG_PPC_BOOK3S_64. While it's annoying to have two symbols that always have the same value, it's not quite annoying enough to bother removing one. However with the arrival of Power9, we now have the situation where CONFIG_PPC_STD_MMU_64 is enabled, but the kernel is running using the Radix MMU - *not* the "standard" MMU. So it is now actively confusing to use it, because it implies that code is disabled or inactive when the Radix MMU is in use, however that is not necessarily true. So s/CONFIG_PPC_STD_MMU_64/CONFIG_PPC_BOOK3S_64/, and do some minor formatting updates of some of the affected lines. This will be a pain for backports, but c'est la vie. Signed-off-by: Michael Ellerman

powerpc: Add purgatory for kexec_file_load() implementation.

2016-11-30T12:15:26Z

This purgatory implementation is based on the versions from kexec-tools and kexec-lite, with additional changes. Signed-off-by: Thiago Jung Bauermann Signed-off-by: Michael Ellerman

powerpc/64/kexec: Remove BookE special default_machine_kexec_prepare()

2016-09-22T21:54:18Z

The only difference is now the TCE table check which doesn't need to be ifdef'ed out, it will basically do nothing on BookE (it is only useful for ancient IBM machines). Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman

powerpc/64/kexec: Copy image with MMU off when possible

2016-09-22T21:54:18Z

Currently we turn the MMU off after copying the image, and we make sure there is no overlap between the hash table and the target pages in that case. That doesn't work for Radix however. In that case, the page tables are scattered and we can't really enforce that the target of the image isn't overlapping one of them. So instead, let's turn the MMU off before copying the image in radix mode. Thankfully, in radix mode, even under a hypervisor, we know we don't have the same kind of RMA limitations that hash mode has. While at it, also turn the MMU off early when using hash in non-LPAR mode, that way we can get rid of the collision check completely. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Aneesh Kumar K.V Acked-by: Balbir Singh Signed-off-by: Michael Ellerman

powerpc/64/kexec: Fix MMU cleanup on radix

2016-09-22T21:54:17Z

Just using the hash ops won't work anymore since radix will have NULL in there. Instead create an mmu_cleanup_all() function which will do the right thing based on the MMU mode. For Radix, for now I clear UPRT and the PTCR, effectively switching back to Radix with no partition table setup. Currently set it to NULL on BookE thought it might be a good idea to wipe the TLB there (Scott ?) Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Aneesh Kumar K.V Acked-by: Balbir Singh Signed-off-by: Michael Ellerman