Changes in paca.c

17e02586 - docs: move powerpc under arch

Sat, 26 Aug 2023 16:56:08 +0000

docs: move powerpc under archand fix all in-tree references.Architecture-specific documentation is being moved into Documentation/arch/as a way of cleaning up the top-level documentation directory and makingthe docs hierarchy more closely match the source hierarchy.Signed-off-by: Costa Shulyupin Acked-by: Michael Ellerman Signed-off-by: Jonathan Corbet Link: https://lore.kernel.org/r/20230826165737.2101199-1-costa.shul@redhat.com List of files: /linux-6.15/arch/powerpc/kernel/paca.c

7e3a68be - powerpc/64: vmlinux support building with PCREL addresing

Sat, 08 Apr 2023 02:17:51 +0000

powerpc/64: vmlinux support building with PCREL addresingPC-Relative or PCREL addressing is an extension to the ELF ABI whichuses Power ISA v3.1 PC-relative instructions to calculate addresses,rather than the traditional TOC scheme.Add an option to build vmlinux using pcrel addressing. Modules continueto use TOC addressing.- TOC address helpers and r2 are poisoned with -1 when running vmlinux. r2 could be used for something useful once things are ironed out.- Assembly must call C functions with @notoc annotation, or the linker complains aobut a missing nop after the call. This is done with the CFUNC macro introduced earlier.- Boot: with the exception of prom_init, the execution branches to the kernel virtual address early in boot, before any addresses are generated, which ensures 34-bit pcrel addressing does not miss the high PAGE_OFFSET bits. TOC relative addressing has a similar requirement. prom_init does not go to the virtual address and its addresses should not carry over to the post-prom kernel.- Ftrace trampolines are converted from TOC addressing to pcrel addressing, including module ftrace trampolines that currently use the kernel TOC to find ftrace target functions.- BPF function prologue and function calling generation are converted from TOC to pcrel.- copypage_64.S has an interesting problem, prefixed instructions have alignment restrictions so the linker can add padding, which makes the assembler treat the difference between two local labels as non-constant even if alignment is arranged so padding is not required. This may need toolchain help to solve nicely, for now move the prefix instruction out of the alternate patch section to work around it.This reduces kernel text size by about 6%.Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://msgid.link/20230408021752.862660-6-npiggin@gmail.com List of files: /linux-6.15/arch/powerpc/kernel/paca.c

e0d68273 - powerpc: Remove CONFIG_PPC_BOOK3E

Mon, 19 Sep 2022 17:01:33 +0000

powerpc: Remove CONFIG_PPC_BOOK3ECONFIG_PPC_BOOK3E is redundant with CONFIG_PPC_BOOK3E_64.The later is more explicit about the fact that it's a 64 bits target.Remove CONFIG_PPC_BOOK3E.Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/5d0891490813c19cdcfc04678f512ea68cba3e64.1663606876.git.christophe.leroy@csgroup.eu List of files: /linux-6.15/arch/powerpc/kernel/paca.c

f88aabad - Revert "powerpc/rtas: Implement reentrant rtas call"

Wed, 07 Sep 2022 22:01:11 +0000

Revert "powerpc/rtas: Implement reentrant rtas call"At the time this was submitted by Leonardo, I confirmed -- or thoughtI had confirmed -- with PowerVM partition firmware development thatthe following RTAS functions:- ibm,get-xive- ibm,int-off- ibm,int-on- ibm,set-xivewere safe to call on multiple CPUs simultaneously, not only withrespect to themselves as indicated by PAPR, but with arbitrary otherRTAS calls:https://lore.kernel.org/linuxppc-dev/875zcy2v8o.fsf@linux.ibm.com/Recent discussion with firmware development makes it clear that thisis not true, and that the code in commit b664db8e3f97 ("powerpc/rtas:Implement reentrant rtas call") is unsafe, likely explaining severalstrange bugs we've seen in internal testing involving DLPAR andLPM. These scenarios use ibm,configure-connector, whose internal statecan be corrupted by the concurrent use of the "reentrant" functions,leading to symptoms like endless busy statuses from RTAS.Fixes: b664db8e3f97 ("powerpc/rtas: Implement reentrant rtas call")Cc: stable@vger.kernel.org # v5.8+Signed-off-by: Nathan Lynch Reviewed-by: Laurent Dufour Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220907220111.223267-1-nathanl@linux.ibm.com List of files: /linux-6.15/arch/powerpc/kernel/paca.c

f693d38d - powerpc/mm: Remove CONFIG_PPC_MM_SLICES

Sat, 09 Apr 2022 17:17:31 +0000

powerpc/mm: Remove CONFIG_PPC_MM_SLICESCONFIG_PPC_MM_SLICES is always selected by hash book3s/64.CONFIG_PPC_MM_SLICES is never selected by other platforms.Remove it.Signed-off-by: Christophe Leroy Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/dc2cdc204de8978574bf7c02329b6cfc4db0bce7.1649523076.git.christophe.leroy@csgroup.eu List of files: /linux-6.15/arch/powerpc/kernel/paca.c

387e220a - powerpc/64s: Move hash MMU support code under CONFIG_PPC_64S_HASH_MMU

Wed, 01 Dec 2021 14:41:52 +0000

powerpc/64s: Move hash MMU support code under CONFIG_PPC_64S_HASH_MMUCompiling out hash support code when CONFIG_PPC_64S_HASH_MMU=n saves128kB kernel image size (90kB text) on powernv_defconfig minus KVM,350kB on pseries_defconfig minus KVM, 40kB on a tiny config.Signed-off-by: Nicholas Piggin [mpe: Fixup defined(ARCH_HAS_MEMREMAP_COMPAT_ALIGN), which needs CONFIG. Fix radix_enabled() use in setup_initial_memory_limit(). Add some stubs to reduce number of ifdefs.]Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211201144153.2456614-18-npiggin@gmail.com List of files: /linux-6.15/arch/powerpc/kernel/paca.c

3ecc6834 - memblock: rename memblock_free to memblock_phys_free

Fri, 05 Nov 2021 20:43:19 +0000

memblock: rename memblock_free to memblock_phys_freeSince memblock_free() operates on a physical range, make its namereflect it and rename it to memblock_phys_free(), so it will be alogical counterpart to memblock_phys_alloc().The callers are updated with the below semantic patch: @@ expression addr; expression size; @@ - memblock_free(addr, size); + memblock_phys_free(addr, size);Link: https://lkml.kernel.org/r/20210930185031.18648-6-rppt@kernel.orgSigned-off-by: Mike Rapoport Cc: Christophe Leroy Cc: Juergen Gross Cc: Shahab Vahedi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds List of files: /linux-6.15/arch/powerpc/kernel/paca.c

13c7dad9 - powerpc/paca: Remove mm_ctx_id and mm_ctx_slb_addr_limit

Wed, 05 May 2021 14:02:13 +0000

powerpc/paca: Remove mm_ctx_id and mm_ctx_slb_addr_limitmm_ctx_id and mm_ctx_slb_addr_limit are not used anymore.Remove them.Signed-off-by: Christophe Leroy Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/6e1813953da38c452c131fe3e2a2761a0fddb975.1620223303.git.christophe.leroy@csgroup.eu List of files: /linux-6.15/arch/powerpc/kernel/paca.c

a7223f5b - powerpc: Avoid broken GCC attribute((optimize))

Wed, 28 Oct 2020 08:04:33 +0000

powerpc: Avoid broken GCC __attribute__((optimize))Commit 7053f80d9696 ("powerpc/64: Prevent stack protection in earlyboot") introduced a couple of uses of __attribute__((optimize)) withfunction scope, to disable the stack protector in some early bootcode.Unfortunately, and this is documented in the GCC man pages [0],overriding function attributes for optimization is broken, and is onlysupported for debug scenarios, not for production: the problem appearsto be that setting GCC -f flags using this method will cause it toforget about some or all other optimization settings that have beenapplied.So the only safe way to disable the stack protector is to disable itfor the entire source file.[0] https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.htmlFixes: 7053f80d9696 ("powerpc/64: Prevent stack protection in early boot")Signed-off-by: Ard Biesheuvel [mpe: Drop one remaining use of __nostackprotector, reported by snowpatch]Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201028080433.26799-1-ardb@kernel.org List of files: /linux-6.15/arch/powerpc/kernel/paca.c

b710d27b - powerpc/pseries/svm: Fix incorrect check for shared_lppaca_size

Fri, 19 Jun 2020 07:01:13 +0000

powerpc/pseries/svm: Fix incorrect check for shared_lppaca_sizeEarly secure guest boot hits the below crash while booting withvcpus numbers aligned with page boundary for PAGE size of 64kand LPPACA size of 1k i.e 64, 128 etc. Partition configured for 64 cpus. CPU maps initialized for 1 thread per core ------------[ cut here ]------------ kernel BUG at arch/powerpc/kernel/paca.c:89! Oops: Exception in kernel mode, sig: 5 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeriesThis is due to the BUG_ON() for shared_lppaca_total_size equal toshared_lppaca_size. Instead the code should only BUG_ON() if we haveexceeded the total_size, which indicates we've overflowed the array.Fixes: bd104e6db6f0 ("powerpc/pseries/svm: Use shared memory for LPPACA structures")Cc: stable@vger.kernel.org # v5.4+Signed-off-by: Satheesh Rajendran Reviewed-by: Laurent Dufour Reviewed-by: Thiago Jung Bauermann [mpe: Reword change log to clarify we're fixing not removing the check]Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200619070113.16696-1-sathnaga@linux.vnet.ibm.com List of files: /linux-6.15/arch/powerpc/kernel/paca.c

178748b6 - powerpc/pseries/svm: Drop unused align argument in alloc_shared_lppaca() function

Fri, 12 Jun 2020 14:29:53 +0000

powerpc/pseries/svm: Drop unused align argument in alloc_shared_lppaca() functionArgument "align" in alloc_shared_lppaca() was unused inside thefunction. Let's drop it and update code comment for page alignment.Signed-off-by: Satheesh Rajendran Reviewed-by: Thiago Jung Bauermann Reviewed-by: Laurent Dufour [mpe: Massage comment wording/formatting]Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200612142953.135408-1-sathnaga@linux.vnet.ibm.com List of files: /linux-6.15/arch/powerpc/kernel/paca.c

65fddcfc - mm: reorder includes after introduction of linux/pgtable.h

Tue, 09 Jun 2020 04:32:42 +0000

mm: reorder includes after introduction of linux/pgtable.hThe replacement of with made the includeof the latter in the middle of asm includes. Fix this up with the aid ofthe below script and manual adjustments here and there. import sys import re if len(sys.argv) is not 3: print "USAGE: %s

" % (sys.argv[0]) sys.exit(1) hdr_to_move="#include " % sys.argv[2] moved = False in_hdrs = False with open(sys.argv[1], "r") as f: lines = f.readlines() for _line in lines: line = _line.rstrip('') if line == hdr_to_move: continue if line.startswith("#include Signed-off-by: Andrew Morton Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brian Cain Cc: Catalin Marinas Cc: Chris Zankel Cc: "David S. Miller" Cc: Geert Uytterhoeven Cc: Greentime Hu Cc: Greg Ungerer Cc: Guan Xuetao Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Ley Foon Tan Cc: Mark Salter Cc: Matthew Wilcox Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Nick Hu Cc: Paul Walmsley Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Tony Luck Cc: Vincent Chen Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.orgSigned-off-by: Linus Torvalds List of files: /linux-6.15/arch/powerpc/kernel/paca.c

ca5999fd - mm: introduce include/linux/pgtable.h

Tue, 09 Jun 2020 04:32:38 +0000

mm: introduce include/linux/pgtable.hThe include/linux/pgtable.h is going to be the home of generic page tablemanipulation functions.Start with moving asm-generic/pgtable.h to include/linux/pgtable.h andmake the latter include asm/pgtable.h.Signed-off-by: Mike Rapoport Signed-off-by: Andrew Morton Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brian Cain Cc: Catalin Marinas Cc: Chris Zankel Cc: "David S. Miller" Cc: Geert Uytterhoeven Cc: Greentime Hu Cc: Greg Ungerer Cc: Guan Xuetao Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Ley Foon Tan Cc: Mark Salter Cc: Matthew Wilcox Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Nick Hu Cc: Paul Walmsley Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Tony Luck Cc: Vincent Chen Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.orgSigned-off-by: Linus Torvalds List of files: /linux-6.15/arch/powerpc/kernel/paca.c

b664db8e - powerpc/rtas: Implement reentrant rtas call

Mon, 18 May 2020 23:42:45 +0000

powerpc/rtas: Implement reentrant rtas callImplement rtas_call_reentrant() for reentrant rtas-calls:"ibm,int-on", "ibm,int-off",ibm,get-xive" and "ibm,set-xive".On LoPAPR Version 1.1 (March 24, 2016), from 7.3.10.1 to 7.3.10.4,items 2 and 3 say:2 - For the PowerPC External Interrupt option: The * call must bereentrant to the number of processors on the platform.3 - For the PowerPC External Interrupt option: The * argument callbuffer for each simultaneous call must be physically unique.So, these rtas-calls can be called in a lockless way, if usinga different buffer for each cpu doing such rtas call.For this, it was suggested to add the buffer (struct rtas_args)in the PACA struct, so each cpu can have it's own buffer.The PACA struct received a pointer to rtas buffer, which isallocated in the memory range available to rtas 32-bit.Reentrant rtas calls are useful to avoid deadlocks in crashing,where rtas-calls are needed, but some other thread crashed holdingthe rtas.lock.This is a backtrace of a deadlock from a kdump testing environment: #0 arch_spin_lock #1 lock_rtas () #2 rtas_call (token=8204, nargs=1, nret=1, outputs=0x0) #3 ics_rtas_mask_real_irq (hw_irq=4100) #4 machine_kexec_mask_interrupts #5 default_machine_crash_shutdown #6 machine_crash_shutdown #7 __crash_kexec #8 crash_kexec #9 oops_endSigned-off-by: Leonardo Bras [mpe: Move under #ifdef PSERIES to avoid build breakage]Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200518234245.200672-3-leobras.c@gmail.com List of files: /linux-6.15/arch/powerpc/kernel/paca.c

7053f80d - powerpc/64: Prevent stack protection in early boot

Fri, 20 Mar 2020 03:21:16 +0000

powerpc/64: Prevent stack protection in early bootThe previous commit reduced the amount of code that is run before wesetup a paca. However there are still a few remaining functions thatrun with no paca, or worse, with an arbitrary value in r13 that willbe used as a paca pointer.In particular the stack protector canary is stored in the paca, so ifstack protector is activated for any of these functions we will readthe stack canary from wherever r13 points. If r13 happens to pointoutside of memory we will get a machine check / checkstop.For example if we modify initialise_paca() to trigger stackprotection, and then boot in the mambo simulator with r13 poisoned inskiboot before calling the kernel: DEBUG: 19952232: (19952232): INSTRUCTION: PC=0xC0000000191FC1E8: [0x3C4C006D]: addis r2,r12,0x6D [fetch] DEBUG: 19952236: (19952236): INSTRUCTION: PC=0xC00000001807EAD8: [0x7D8802A6]: mflr r12 [fetch] FATAL ERROR: 19952276: (19952276): Check Stop for 0:0: Machine Check with ME bit of MSR off DEBUG: 19952276: (19952276): INSTRUCTION: PC=0xC0000000191FCA7C: [0xE90D0CF8]: ld r8,0xCF8(r13) [Instruction Failed] INFO: 19952276: (19952277): ** Execution stopped: Mambo Error, Machine Check Stop, ** systemsim % bt pc: 0xC0000000191FCA7C initialise_paca+0x54 lr: 0xC0000000191FC22C early_setup+0x44 stack:0x00000000198CBED0 0x0 +0x0 stack:0x00000000198CBF00 0xC0000000191FC22C early_setup+0x44 stack:0x00000000198CBF90 0x1801C968 +0x1801C968So annotate the relevant functions to ensure stack protection is neverenabled for them.Fixes: 06ec27aea9fc ("powerpc/64: add stack protector support")Cc: stable@vger.kernel.org # v4.20+Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200320032116.1024773-2-mpe@ellerman.id.au List of files: /linux-6.15/arch/powerpc/kernel/paca.c

d4a8e986 - powerpc/64: Setup a paca before parsing device tree etc.

Fri, 20 Mar 2020 03:21:15 +0000

powerpc/64: Setup a paca before parsing device tree etc.Currently we set up the paca after parsing the device tree for CPUfeatures. Prior to that, r13 contains random data, which means thereis random data in r13 while we're running the generic dt parsing code.This random data varies depending on whether we boot through a vmlinuxor a zImage: for the vmlinux case it's usually around zero, but forzImages we see random values like 912a72603d420015.This is poor practice, and can also lead to difficult-to-debugcrashes. For example, when kcov is enabled, the kcov instrumentationattempts to read preempt_count out of the current task, which goes viathe paca. This then crashes in the zImage case.Similarly stack protector can cause crashes if r13 is bogus, byreading from the stack canary in the paca.To resolve this: - move the paca setup to before the CPU feature parsing. - because we no longer have access to CPU feature flags in paca setup, change the HV feature test in the paca setup path to consider the actual value of the MSR rather than the CPU feature.Translations get switched on once we leave early_setup, so I thinkwe'd already catch any other cases where the paca or task aren't setup.Boot tested on a P9 guest and host.Fixes: fb0b0a73b223 ("powerpc: Enable kcov")Fixes: 06ec27aea9fc ("powerpc/64: add stack protector support")Cc: stable@vger.kernel.org # v4.20+Reviewed-by: Andrew Donnellan Suggested-by: Michael Ellerman Signed-off-by: Daniel Axtens [mpe: Reword comments & change log a bit to mention stack protector]Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200320032116.1024773-1-mpe@ellerman.id.au List of files: /linux-6.15/arch/powerpc/kernel/paca.c

bd104e6d - powerpc/pseries/svm: Use shared memory for LPPACA structures

Tue, 20 Aug 2019 02:13:18 +0000

powerpc/pseries/svm: Use shared memory for LPPACA structuresLPPACA structures need to be shared with the host. Hence they need to be inshared memory. Instead of allocating individual chunks of memory for agiven structure from memblock, a contiguous chunk of memory is allocatedand then converted into shared memory. Subsequent allocation requests willcome from the contiguous chunk which will be always shared memory for allstructures.While we are able to use a kmem_cache constructor for the Debug Trace Log,LPPACAs are allocated very early in the boot process (before SLUB isavailable) so we need to use a simpler scheme here.Introduce helper is_svm_platform() which uses the S bit of the MSR to tellwhether we're running as a secure guest.Signed-off-by: Anshuman Khandual Signed-off-by: Thiago Jung Bauermann Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190820021326.6884-9-bauerman@linux.ibm.com List of files: /linux-6.15/arch/powerpc/kernel/paca.c

e311a92d - powerpc/pseries: Add and use LPPACA_SIZE constant

Tue, 20 Aug 2019 02:13:17 +0000

powerpc/pseries: Add and use LPPACA_SIZE constantHelps document what the hard-coded number means.Also take the opportunity to fix an #endif comment.Suggested-by: Alexey Kardashevskiy Signed-off-by: Thiago Jung Bauermann Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190820021326.6884-8-bauerman@linux.ibm.com List of files: /linux-6.15/arch/powerpc/kernel/paca.c

2874c5fd - treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Mon, 27 May 2019 06:55:01 +0000

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Based 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 versionextracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-laterhas 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.orgLink: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.deSigned-off-by: Greg Kroah-Hartman List of files: /linux-6.15/arch/powerpc/kernel/paca.c

60458fba - powerpc/mm: Add helpers for accessing hash translation related variables

Wed, 17 Apr 2019 13:03:48 +0000

powerpc/mm: Add helpers for accessing hash translation related variablesWe want to switch to allocating them runtime only when hash translation isenabled. Add helpers so that both book3s and nohash can be adapted toupcoming change easily.Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman List of files: /linux-6.15/arch/powerpc/kernel/paca.c