kernel/linux.git/arch/powerpc/include/asm/exception-64e.h, branch v6.7

powerpc/code-patching: Move patch_exception() outside code-patching.c

2021-12-23T11:36:55+00:00

patch_exception() is dedicated to book3e/64 is nothing more than a normal use of patch_branch(), so move it into a place dedicated to book3e/64. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/0968622b98b1fb51838c35b844c42ad6609de62e.1638446239.git.christophe.leroy@csgroup.eu

powerpc/64e: Drop dead BOOK3E_MMU_TLB_STATS code

2020-07-29T11:08:12+00:00

This code was merged 11 years ago in commit 13363ab9b9d0 ("powerpc: Add definitions used by exception handling on 64-bit Book3E") but was never able to be built because CONFIG_BOOK3E_MMU_TLB_STATS never existed. Remove it. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200724131728.1643966-4-mpe@ellerman.id.au

powerpc: Select ARCH_HAS_MEMBARRIER_SYNC_CORE

2020-07-23T07:43:23+00:00

powerpc return from interrupt and return from system call sequences are context synchronising. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200716013522.338318-1-npiggin@gmail.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/64: Add macros for annotating the destination of rfid/hrfid

2018-01-09T16:07:30+00:00

The rfid/hrfid ((Hypervisor) Return From Interrupt) instruction is used for switching from the kernel to userspace, and from the hypervisor to the guest kernel. However it can and is also used for other transitions, eg. from real mode kernel code to virtual mode kernel code, and it's not always clear from the code what the destination context is. To make it clearer when reading the code, add macros which encode the expected destination context. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

powerpc/e6500: hw tablewalk: make sure we invalidate and write to the same tlb entry

2015-10-27T23:14:40+00:00

In order to workaround Erratum A-008139, we have to invalidate the tlb entry with tlbilx before overwriting. Due to the performance consideration, we don't add any memory barrier when acquire/release the tcd lock. This means the two load instructions for esel_next do have the possibility to return different value. This is definitely not acceptable due to the Erratum A-008139. We have two options to fix this issue: a) Add memory barrier when acquire/release tcd lock to order the load/store to esel_next. b) Just make sure to invalidate and write to the same tlb entry and tolerate the race that we may get the wrong value and overwrite the tlb entry just updated by the other thread. We observe better performance using option b. So reserve an additional register to save the value of the esel_next. Signed-off-by: Kevin Hao Signed-off-by: Scott Wood

powerpc/book3e: support CONFIG_RELOCATABLE

2015-10-27T23:13:27+00:00

book3e is different with book3s since 3s includes the exception vectors code in head_64.S as it relies on absolute addressing which is only possible within this compilation unit. So we have to get that label address with got. And when boot a relocated kernel, we should reset ipvr properly again after .relocate. Signed-off-by: Tiejun Chen [scottwood: cleanup and ifdef removal] Signed-off-by: Scott Wood

powerpc: No need to use dot symbols when branching to a function

2014-04-23T00:05:16+00:00

binutils is smart enough to know that a branch to a function descriptor is actually a branch to the functions text address. Alan tells me that binutils has been doing this for 9 years. Signed-off-by: Anton Blanchard

powerpc/booke64: Use SPRG_TLB_EXFRAME on bolted handlers

2014-03-20T00:57:15+00:00

While bolted handlers (including e6500) do not need to deal with a TLB miss recursively causing another TLB miss, nested TLB misses can still happen with crit/mc/debug exceptions -- so we still need to honor SPRG_TLB_EXFRAME. We don't need to spend time modifying it in the TLB miss fastpath, though -- the special level exception will handle that. Signed-off-by: Scott Wood Cc: Mihai Caraman Cc: kvm-ppc@vger.kernel.org

powerpc/booke64: Use SPRG7 for VDSO

2014-03-20T00:57:14+00:00

Previously SPRG3 was marked for use by both VDSO and critical interrupts (though critical interrupts were not fully implemented). In commit 8b64a9dfb091f1eca8b7e58da82f1e7d1d5fe0ad ("powerpc/booke64: Use SPRG0/3 scratch for bolted TLB miss & crit int"), Mihai Caraman made an attempt to resolve this conflict by restoring the VDSO value early in the critical interrupt, but this has some issues: - It's incompatible with EXCEPTION_COMMON which restores r13 from the by-then-overwritten scratch (this cost me some debugging time). - It forces critical exceptions to be a special case handled differently from even machine check and debug level exceptions. - It didn't occur to me that it was possible to make this work at all (by doing a final "ld r13, PACA_EXCRIT+EX_R13(r13)") until after I made (most of) this patch. :-) It might be worth investigating using a load rather than SPRG on return from all exceptions (except TLB misses where the scratch never leaves the SPRG) -- it could save a few cycles. Until then, let's stick with SPRG for all exceptions. Since we cannot use SPRG4-7 for scratch without corrupting the state of a KVM guest, move VDSO to SPRG7 on book3e. Since neither SPRG4-7 nor critical interrupts exist on book3s, SPRG3 is still used for VDSO there. Signed-off-by: Scott Wood Cc: Mihai Caraman Cc: Anton Blanchard Cc: Paul Mackerras Cc: kvm-ppc@vger.kernel.org