Commit Graph

200 Commits

Author SHA1 Message Date
Linus Torvalds
4ad0a4c234 powerpc updates for 6.6
- Add HOTPLUG_SMT support (/sys/devices/system/cpu/smt) and honour the
    configured SMT state when hotplugging CPUs into the system.
 
  - Combine final TLB flush and lazy TLB mm shootdown IPIs when using the Radix
    MMU to avoid a broadcast TLBIE flush on exit.
 
  - Drop the exclusion between ptrace/perf watchpoints, and drop the now unused
    associated arch hooks.
 
  - Add support for the "nohlt" command line option to disable CPU idle.
 
  - Add support for -fpatchable-function-entry for ftrace, with GCC >= 13.1.
 
  - Rework memory block size determination, and support 256MB size on systems
    with GPUs that have hotpluggable memory.
 
  - Various other small features and fixes.
 
 Thanks to: Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira Rajeev,
 Benjamin Gray, Christophe Leroy, Frederic Barrat, Gautam Menghani, Geoff Levand,
 Hari Bathini, Immad Mir, Jialin Zhang, Joel Stanley, Jordan Niethe, Justin
 Stitt, Kajol Jain, Kees Cook, Krzysztof Kozlowski, Laurent Dufour, Liang He,
 Linus Walleij, Mahesh Salgaonkar, Masahiro Yamada, Michal Suchanek, Nageswara
 R Sastry, Nathan Chancellor, Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nick
 Desaulniers, Omar Sandoval, Randy Dunlap, Reza Arbab, Rob Herring, Russell
 Currey, Sourabh Jain, Thomas Gleixner, Trevor Woerner, Uwe Kleine-König, Vaibhav
 Jain, Xiongfeng Wang, Yuan Tan, Zhang Rui, Zheng Zengkai.
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Merge tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Add HOTPLUG_SMT support (/sys/devices/system/cpu/smt) and honour the
   configured SMT state when hotplugging CPUs into the system

 - Combine final TLB flush and lazy TLB mm shootdown IPIs when using the
   Radix MMU to avoid a broadcast TLBIE flush on exit

 - Drop the exclusion between ptrace/perf watchpoints, and drop the now
   unused associated arch hooks

 - Add support for the "nohlt" command line option to disable CPU idle

 - Add support for -fpatchable-function-entry for ftrace, with GCC >=
   13.1

 - Rework memory block size determination, and support 256MB size on
   systems with GPUs that have hotpluggable memory

 - Various other small features and fixes

Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira
Rajeev, Benjamin Gray, Christophe Leroy, Frederic Barrat, Gautam
Menghani, Geoff Levand, Hari Bathini, Immad Mir, Jialin Zhang, Joel
Stanley, Jordan Niethe, Justin Stitt, Kajol Jain, Kees Cook, Krzysztof
Kozlowski, Laurent Dufour, Liang He, Linus Walleij, Mahesh Salgaonkar,
Masahiro Yamada, Michal Suchanek, Nageswara R Sastry, Nathan Chancellor,
Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nick Desaulniers, Omar
Sandoval, Randy Dunlap, Reza Arbab, Rob Herring, Russell Currey, Sourabh
Jain, Thomas Gleixner, Trevor Woerner, Uwe Kleine-König, Vaibhav Jain,
Xiongfeng Wang, Yuan Tan, Zhang Rui, and Zheng Zengkai.

* tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (135 commits)
  macintosh/ams: linux/platform_device.h is needed
  powerpc/xmon: Reapply "Relax frame size for clang"
  powerpc/mm/book3s64: Use 256M as the upper limit with coherent device memory attached
  powerpc/mm/book3s64: Fix build error with SPARSEMEM disabled
  powerpc/iommu: Fix notifiers being shared by PCI and VIO buses
  powerpc/mpc5xxx: Add missing fwnode_handle_put()
  powerpc/config: Disable SLAB_DEBUG_ON in skiroot
  powerpc/pseries: Remove unused hcall tracing instruction
  powerpc/pseries: Fix hcall tracepoints with JUMP_LABEL=n
  powerpc: dts: add missing space before {
  powerpc/eeh: Use pci_dev_id() to simplify the code
  powerpc/64s: Move CPU -mtune options into Kconfig
  powerpc/powermac: Fix unused function warning
  powerpc/pseries: Rework lppaca_shared_proc() to avoid DEBUG_PREEMPT
  powerpc: Don't include lppaca.h in paca.h
  powerpc/pseries: Move hcall_vphn() prototype into vphn.h
  powerpc/pseries: Move VPHN constants into vphn.h
  cxl: Drop unused detach_spa()
  powerpc: Drop zalloc_maybe_bootmem()
  powerpc/powernv: Use struct opal_prd_msg in more places
  ...
2023-08-31 12:43:10 -07:00
Masahiro Yamada
3eb3f168e8 powerpc: remove unneeded #include <asm/export.h>
There is no EXPORT_SYMBOL line there, hence #include <asm/export.h>
is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230806150954.394189-1-masahiroy@kernel.org
2023-08-16 23:54:48 +10:00
Michael Ellerman
2dc0bc1138 powerpc/64e: Fix secondary thread bringup for ELFv2 kernels
When booting on e6500 with an ELF v2 ABI kernel, the secondary threads do
not start correctly:

    [    0.051118] smp: Bringing up secondary CPUs ...
    [    5.072700] Processor 1 is stuck.

This occurs because the startup code is written to use function
descriptors when loading the entry point for the secondary threads. When
building with ELF v2 ABI there are no function descriptors, and the code
loads junk values for the entry point address.

Fix it by using ppc_function_entry() in C, and DOTSYM() in asm, both of
which work correctly for ELF v2 ABI as well as ELF v1 ABI kernels.

Fixes: 8c5fa3b5c4 ("powerpc/64: Make ELFv2 the default for big-endian builds")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230801102650.48705-1-mpe@ellerman.id.au
2023-08-01 21:01:27 +10:00
Nicholas Piggin
7e3a68be42 powerpc/64: vmlinux support building with PCREL addresing
PC-Relative or PCREL addressing is an extension to the ELF ABI which
uses 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 continue
to 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 <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-6-npiggin@gmail.com
2023-04-20 12:59:21 +10:00
Nicholas Piggin
4e991e3c16 powerpc: add CFUNC assembly label annotation
This macro is to be used in assembly where C functions are called.
pcrel addressing mode requires branches to functions with a
localentry value of 1 to have either a trailing nop or @notoc.
This macro permits the latter without changing callers.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add dummy definitions to fix selftests build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-5-npiggin@gmail.com
2023-04-20 12:54:24 +10:00
Nicholas Piggin
b270bebd34 powerpc/64s: Run at the kernel virtual address earlier in boot
This mostly consolidates the Book3E and Book3S behaviour in boot WRT
executing from the physical or virtual address.

Book3E sets up kernel virtual linear map in start_initialization_book3e
and runs from the virtual linear alias after that. This change makes
Book3S begin to execute from the virtual alias at the same point. Book3S
can not use its MMU for that at this point, but when the MMU is disabled,
the virtual linear address correctly aliases to physical memory because
the top bits of the address are ignored with MMU disabled.

Secondaries execute from the virtual address similarly early.

This reduces the differences between subarchs, but the main motivation
was to enable the PC-relative addressing ABI for Book3S, where pointer
calculations must execute from the virtual address or the top bits of
the pointer will be lost. This is similar to the requirement the TOC
relative addressing already has that the TOC pointer use its virtual
address.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-3-npiggin@gmail.com
2023-04-20 12:23:14 +10:00
Nicholas Piggin
4f18b9e6ca powerpc/64: Move initial base and TOC pointer calculation
A later change moves the non-prom case to run at the virtual address
earlier, which calls for virtual TOC and kernel base. Split these two
calculations for prom and non-prom to make that change simpler.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Retain relative_toc call for start_initialization_book3e]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408021752.862660-2-npiggin@gmail.com
2023-04-20 12:23:14 +10:00
Sathvika Vasireddy
38d73b671a powerpc/64: Fix unannotated intra-function call warning
objtool throws the following warning:
  arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x6128:
  unannotated intra-function call

Fix the warning by annotating start_initialization_book3s symbol with the
SYM_FUNC_START_LOCAL and SYM_FUNC_END macros.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
Fixes: 58f24eea52 ("powerpc/64s: Refactor initialisation after prom")
Suggested-by: Josh Poimboeuf <jpoimboe@kernel.org>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230217043226.1020041-1-sv@linux.ibm.com
2023-02-17 22:11:55 +11:00
Nicholas Piggin
ffc8e90dec powerpc/64e: Simplify address calculation in secondary hold loop
As the earlier comment explains, __secondary_hold_spinloop does not have
to be accessed at its virtual address, slightly simplifying code.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230203113858.1152093-4-npiggin@gmail.com
2023-02-10 22:17:36 +11:00
Nicholas Piggin
58f24eea52 powerpc/64s: Refactor initialisation after prom
Move some basic Book3S initialisation after prom to a function similar
to what Book3E looks like. Book3E returns from this function at the
virtual address mapping, and Book3S will do the same in a later change,
so making them look similar helps with that.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230203113858.1152093-3-npiggin@gmail.com
2023-02-10 22:17:36 +11:00
Michael Ellerman
f24f21c412 Merge branch 'topic/objtool' into next
Merge the powerpc objtool support, which we were keeping in a topic
branch in case of any merge conflicts.
2022-12-08 23:57:47 +11:00
Nicholas Piggin
90f1b43196 powerpc: allow minimum sized kernel stack frames
This affects only 64-bit ELFv2 kernels, and reduces the minimum
asm-created stack frame size from 112 to 32 byte on those kernels.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221127124942.1665522-16-npiggin@gmail.com
2022-12-02 17:54:09 +11:00
Sathvika Vasireddy
29a011fc79 powerpc: Fix objtool unannotated intra-function call warnings
Objtool throws unannotated intra-function call warnings in the following
assembly files:

arch/powerpc/kernel/vector.o: warning: objtool: .text+0x53c: unannotated intra-function call

arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x60: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x124: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x5d4: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x5dc: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0xcb8: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0xd0c: unannotated intra-function call
arch/powerpc/kvm/book3s_hv_rmhandlers.o: warning: objtool: .text+0x1030: unannotated intra-function call

arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x358: unannotated intra-function call
arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x728: unannotated intra-function call
arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x4d94: unannotated intra-function call
arch/powerpc/kernel/head_64.o: warning: objtool: .text+0x4ec4: unannotated intra-function call

arch/powerpc/kvm/book3s_hv_interrupts.o: warning: objtool: .text+0x6c: unannotated intra-function call
arch/powerpc/kernel/misc_64.o: warning: objtool: .text+0x64: unannotated intra-function call

Objtool does not add STT_NOTYPE symbols with size 0 to the rbtree, which
is why find_call_destination() function is not able to find the
destination symbol for 'bl' instruction. For such symbols, objtool is
throwing unannotated intra-function call warnings in assembly files. Fix
these warnings by annotating those symbols with SYM_FUNC_START_LOCAL and
SYM_FUNC_END macros, inorder to set symbol type to STT_FUNC and symbol
size accordingly.

Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221114175754.1131267-4-sv@linux.ibm.com
2022-11-15 20:11:47 +11:00
Linus Torvalds
d4013bc4d4 bitmap patches for v6.1-rc1
From Phil Auld:
 drivers/base: Fix unsigned comparison to -1 in CPUMAP_FILE_MAX_BYTES
 
 From me:
 cpumask: cleanup nr_cpu_ids vs nr_cpumask_bits mess
 
 This series cleans that mess and adds new config FORCE_NR_CPUS that
 allows to optimize cpumask subsystem if the number of CPUs is known
 at compile-time.
 
 From me:
 lib: optimize find_bit() functions
 
 Reworks find_bit() functions based on new FIND_{FIRST,NEXT}_BIT() macros.
 
 From me:
 lib/find: add find_nth_bit()
 
 Adds find_nth_bit(), which is ~70 times faster than bitcounting with
 for_each() loop:
         for_each_set_bit(bit, mask, size)
                 if (n-- == 0)
                         return bit;
 
 Also adds bitmap_weight_and() to let people replace this pattern:
 	tmp = bitmap_alloc(nbits);
 	bitmap_and(tmp, map1, map2, nbits);
 	weight = bitmap_weight(tmp, nbits);
 	bitmap_free(tmp);
 with a single bitmap_weight_and() call.
 
 From me:
 cpumask: repair cpumask_check()
 
 After switching cpumask to use nr_cpu_ids, cpumask_check() started
 generating many false-positive warnings. This series fixes it.
 
 From Valentin Schneider:
 bitmap,cpumask: Add for_each_cpu_andnot() and for_each_cpu_andnot()
 
 Extends the API with one more function and applies it in sched/core.
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Merge tag 'bitmap-6.1-rc1' of https://github.com/norov/linux

Pull bitmap updates from Yury Norov:

 - Fix unsigned comparison to -1 in CPUMAP_FILE_MAX_BYTES (Phil Auld)

 - cleanup nr_cpu_ids vs nr_cpumask_bits mess (me)

   This series cleans that mess and adds new config FORCE_NR_CPUS that
   allows to optimize cpumask subsystem if the number of CPUs is known
   at compile-time.

 - optimize find_bit() functions (me)

   Reworks find_bit() functions based on new FIND_{FIRST,NEXT}_BIT()
   macros.

 - add find_nth_bit() (me)

   Adds find_nth_bit(), which is ~70 times faster than bitcounting with
   for_each() loop:

	for_each_set_bit(bit, mask, size)
		if (n-- == 0)
			return bit;

   Also adds bitmap_weight_and() to let people replace this pattern:

	tmp = bitmap_alloc(nbits);
	bitmap_and(tmp, map1, map2, nbits);
	weight = bitmap_weight(tmp, nbits);
	bitmap_free(tmp);

   with a single bitmap_weight_and() call.

 - repair cpumask_check() (me)

   After switching cpumask to use nr_cpu_ids, cpumask_check() started
   generating many false-positive warnings. This series fixes it.

 - Add for_each_cpu_andnot() and for_each_cpu_andnot() (Valentin
   Schneider)

   Extends the API with one more function and applies it in sched/core.

* tag 'bitmap-6.1-rc1' of https://github.com/norov/linux: (28 commits)
  sched/core: Merge cpumask_andnot()+for_each_cpu() into for_each_cpu_andnot()
  lib/test_cpumask: Add for_each_cpu_and(not) tests
  cpumask: Introduce for_each_cpu_andnot()
  lib/find_bit: Introduce find_next_andnot_bit()
  cpumask: fix checking valid cpu range
  lib/bitmap: add tests for for_each() loops
  lib/find: optimize for_each() macros
  lib/bitmap: introduce for_each_set_bit_wrap() macro
  lib/find_bit: add find_next{,_and}_bit_wrap
  cpumask: switch for_each_cpu{,_not} to use for_each_bit()
  net: fix cpu_max_bits_warn() usage in netif_attrmask_next{,_and}
  cpumask: add cpumask_nth_{,and,andnot}
  lib/bitmap: remove bitmap_ord_to_pos
  lib/bitmap: add tests for find_nth_bit()
  lib: add find_nth{,_and,_andnot}_bit()
  lib/bitmap: add bitmap_weight_and()
  lib/bitmap: don't call __bitmap_weight() in kernel code
  tools: sync find_bit() implementation
  lib/find_bit: optimize find_next_bit() functions
  lib/find_bit: create find_first_zero_bit_le()
  ...
2022-10-10 12:49:34 -07:00
Nicholas Piggin
e1100cee05 powerpc/64s/interrupt: halt early boot interrupts if paca is not set up
Ensure r13 is zero from very early in boot until it gets set to the
boot paca pointer. This allows early program and mce handlers to halt
if there is no valid paca, rather than potentially run off into the
weeds. This preserves register and memory contents for low level
debugging tools.

Nothing could be printed to console at this point in any case because
even udbg is only set up after the boot paca is set, so this shouldn't
be missed.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220926055620.2676869-6-npiggin@gmail.com
2022-09-28 19:22:13 +10:00
Nicholas Piggin
8e93fb33c8 powerpc/64: provide a helper macro to load r2 with the kernel TOC
A later change stops the kernel using r2 and loads it with a poison
value.  Provide a PACATOC loading abstraction which can hide this
detail.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220926034057.2360083-5-npiggin@gmail.com
2022-09-28 19:22:12 +10:00
Nicholas Piggin
17773afdcd powerpc/64: use 32-bit immediate for STACK_FRAME_REGS_MARKER
Using a 32-bit constant for this marker allows it to be loaded with
two ALU instructions, like 32-bit. This avoids a TOC entry and a
TOC load that depends on the r2 value that has just been loaded from
the PACA.

This changes the value for 32-bit as well, so both have the same
value in the low 4 bytes and 64-bit has 0 in the top bytes.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220926034057.2360083-2-npiggin@gmail.com
2022-09-28 19:22:12 +10:00
Christophe Leroy
e0d68273d7 powerpc: Remove CONFIG_PPC_BOOK3E
CONFIG_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 <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5d0891490813c19cdcfc04678f512ea68cba3e64.1663606876.git.christophe.leroy@csgroup.eu
2022-09-26 23:00:13 +10:00
Yury Norov
546a073d62 powerpc/64: don't refer nr_cpu_ids in asm code when it's undefined
generic_secondary_common_init() calls LOAD_REG_ADDR(r7, nr_cpu_ids)
conditionally on CONFIG_SMP. However, if 'NR_CPUS == 1', kernel doesn't
use the nr_cpu_ids, and in C code, it's just:
  #if NR_CPUS == 1
  #define nr_cpu_ids
  ...

This series makes declaration of nr_cpu_ids conditional on NR_CPUS == 1,
and that reveals the issue, because compiler can't link the
LOAD_REG_ADDR(r7, nr_cpu_ids) against nonexisting symbol.

Current code looks unsafe for those who build kernel with CONFIG_SMP=y and
NR_CPUS == 1. This is weird configuration, but not disallowed.

Fix the linker error by replacing LOAD_REG_ADDR() with LOAD_REG_IMMEDIATE()
conditionally on NR_CPUS == 1.

As the following patch adds CONFIG_FORCE_NR_CPUS option that has the
similar effect on nr_cpu_ids, make the generic_secondary_common_init()
conditional on it too.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-09-20 16:11:44 -07:00
Christophe Leroy
c7b9ed7c34 powerpc/64e: KASAN Full support for BOOK3E/64
We now have memory organised in a way that allows
implementing KASAN.

Unlike book3s/64, book3e always has translation active so the only
thing needed to use KASAN is to setup an early zero shadow mapping
just after setting a stack pointer and before calling early_setup().

The memory layout is now as follows

   +------------------------+  Kernel virtual map end (0xc000200000000000)
   |                        |
   |    16TB of KASAN map   |
   |                        |
   +------------------------+  Kernel KASAN shadow map start
   |                        |
   |    16TB of IO map      |
   |                        |
   +------------------------+  Kernel IO map start
   |                        |
   |    16TB of vmemmap     |
   |                        |
   +------------------------+  Kernel vmemmap start
   |                        |
   |    16TB of vmap        |
   |                        |
   +------------------------+  Kernel virt start (0xc000100000000000)
   |                        |
   |    64TB of linear mem  |
   |                        |
   +------------------------+  Kernel linear (0xc.....)

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0bef8beda27baf71e3b9e8b13e620fba6e19499b.1656427701.git.christophe.leroy@csgroup.eu
2022-06-29 17:04:15 +10:00
Michael Ellerman
87c78b612f powerpc: Fix all occurences of "the the"
Rather than waiting for the bots to fix these one-by-one, fix all
occurences of "the the" throughout arch/powerpc.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220518142629.513007-1-mpe@ellerman.id.au
2022-05-22 15:59:43 +10:00
Christophe Leroy
7d40aff821 powerpc: Replace PPC64_ELF_ABI_v{1/2} by CONFIG_PPC64_ELF_ABI_V{1/2}
Replace all uses of PPC64_ELF_ABI_v1 and PPC64_ELF_ABI_v2 by
resp CONFIG_PPC64_ELF_ABI_V1 and CONFIG_PPC64_ELF_ABI_V2.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ba13d59e8c50bc9aa6328f1c7f0c0d0278e0a3a7.1652074503.git.christophe.leroy@csgroup.eu
2022-05-19 23:11:29 +10:00
Daniel Axtens
d72c4a36d7 powerpc/64/asm: Do not reassign labels
The LLVM integrated assembler really does not like us reassigning things
to the same label:

<instantiation>:7:9: error: invalid reassignment of non-absolute variable 'fs_label'

This happens across a bunch of platforms:
https://github.com/ClangBuiltLinux/linux/issues/1043
https://github.com/ClangBuiltLinux/linux/issues/1008
https://github.com/ClangBuiltLinux/linux/issues/920
https://github.com/ClangBuiltLinux/linux/issues/1050

There is no hope of getting this fixed in LLVM (see
https://github.com/ClangBuiltLinux/linux/issues/1043#issuecomment-641571200
and https://bugs.llvm.org/show_bug.cgi?id=47798#c1 )
so if we want to build with LLVM_IAS, we need to hack
around it ourselves.

For us the big problem comes from this:

\#define USE_FIXED_SECTION(sname)				\
	fs_label = start_##sname;				\
	fs_start = sname##_start;				\
	use_ftsec sname;

\#define USE_TEXT_SECTION()
	fs_label = start_text;					\
	fs_start = text_start;					\
	.text

and in particular fs_label.

This works around it by not setting those 'variables' and requiring
that users of the variables instead track for themselves what section
they are in. This isn't amazing, by any stretch, but it gets us further
in the compilation.

Note that even though users have to keep track of the section, using
a wrong one produces an error with both binutils and llvm which prevents
from using wrong section at the compile time:

llvm error example:

AS      arch/powerpc/kernel/head_64.o
<unknown>:0: error: Cannot represent a difference across sections
make[3]: *** [/home/aik/p/kernels-llvm/llvm/scripts/Makefile.build:388: arch/powerpc/kernel/head_64.o] Error 1

binutils error example:

/home/aik/p/kernels-llvm/llvm/arch/powerpc/kernel/exceptions-64s.S: Assembler messages:
/home/aik/p/kernels-llvm/llvm/arch/powerpc/kernel/exceptions-64s.S:1974: Error: can't resolve `system_call_common' {.text section} - `start_r
eal_vectors' {.head.text.real_vectors section}
make[3]: *** [/home/aik/p/kernels-llvm/llvm/scripts/Makefile.build:388: arch/powerpc/kernel/head_64.o] Error 1

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211221055904.555763-5-aik@ozlabs.ru
2021-12-23 22:35:12 +11:00
Alan Modra
a3ad84da07 powerpc/toc: Future proof kernel toc
This patch future-proofs the kernel against linker changes that might
put the toc pointer at some location other than .got+0x8000, by
replacing __toc_start+0x8000 with .TOC. throughout.  If the kernel's
idea of the toc pointer doesn't agree with the linker, bad things
happen.

prom_init.c code relocating its toc is also changed so that a symbolic
__prom_init_toc_start toc-pointer relative address is calculated
rather than assuming that it is always at toc-pointer - 0x8000.  The
length calculations loading values from the toc are also avoided.
It's a little incestuous to do that with unreloc_toc picking up
adjusted values (which is fine in practice, they both adjust by the
same amount if all goes well).

I've also changed the way .got is aligned in vmlinux.lds and
zImage.lds, mostly so that dumping out section info by objdump or
readelf plainly shows the alignment is 256.  This linker script
feature was added 2005-09-27, available in FSF binutils releases from
2.17 onwards.  Should be safe to use in the kernel, I think.

Finally, put *(.got) before the prom_init.o entry which only needs
*(.toc), so that the GOT header goes in the correct place.  I don't
believe this makes any difference for the kernel as it would for
dynamic objects being loaded by ld.so.  That change is just to stop
lusers who blindly copy kernel scripts being led astray.  Of course,
this change needs the prom_init.c changes.

Some notes on .toc and .got.

.toc is a compiler generated section of addresses.  .got is a linker
generated section of addresses, generally built when the linker sees
R_*_*GOT* relocations.  In the case of powerpc64 ld.bfd, there are
multiple generated .got sections, one per input object file.  So you
can somewhat reasonably write in a linker script an input section
statement like *prom_init.o(.got .toc) to mean "the .got and .toc
section for files matching *prom_init.o".  On other architectures that
doesn't make sense, because the linker generally has just one .got
section.  Even on powerpc64, note well that the GOT entries for
prom_init.o may be merged with GOT entries from other objects.  That
means that if prom_init.o references, say, _end via some GOT
relocation, and some other object also references _end via a GOT
relocation, the GOT entry for _end may be in the range
__prom_init_toc_start to __prom_init_toc_end and if the kernel does
something special to GOT/TOC entries in that range then the value of
_end as seen by objects other than prom_init.o will be affected.  On
the other hand the GOT entry for _end may not be in the range
__prom_init_toc_start to __prom_init_toc_end.  Which way it turns out
is deterministic but a detail of linker operation that should not be
relied on.

A feature of ld.bfd is that input .toc (and .got) sections matching
one linker input section statement may be sorted, to put entries used
by small-model code first, near the toc base.  This is why scripts for
powerpc64 normally use *(.got .toc) rather than *(.got) *(.toc), since
the first form allows more freedom to sort.

Another feature of ld.bfd is that indirect addressing sequences using
the GOT/TOC may be edited by the linker to relative addressing.  In
many cases relative addressing would be emitted by gcc for
-mcmodel=medium if you appropriately decorate variable declarations
with non-default visibility.

The original patch is here:
https://lore.kernel.org/linuxppc-dev/20210310034813.GM6042@bubble.grove.modra.org/

Signed-off-by: Alan Modra <amodra@au1.ibm.com>
[aik: removed non-relocatable which is gone in 24d33ac5b8]
[aik: added <=2.24 check]
[aik: because of llvm-as, kernel_toc_addr() uses "mr" instead of global register variable]
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211221055904.555763-2-aik@ozlabs.ru
2021-12-23 22:35:01 +11:00
Hari Bathini
8119cefd9a powerpc/kexec: blacklist functions called in real mode for kprobe
As kprobe does not handle events happening in real mode, blacklist the
functions that only get called in real mode or in kexec sequence with
MMU turned off.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/162626687834.155313.4692863392927831843.stgit@hbathini-workstation.ibm.com
2021-07-26 20:38:51 +10:00
Nicholas Piggin
e754f4d13e powerpc/64: move interrupt return asm to interrupt_64.S
The next patch would like to move interrupt return assembly code to a low
location before general text, so move it into its own file and include via
head_64.S

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210617155116.2167984-7-npiggin@gmail.com
2021-06-25 00:06:55 +10:00
Christophe Leroy
e72421a085 powerpc: Define swapper_pg_dir[] in C
Don't duplicate swapper_pg_dir[] in each platform's head.S

Define it in mm/pgtable.c

Define MAX_PTRS_PER_PGD because on book3s/64 PTRS_PER_PGD is
not a constant.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5e3f1b8a4695c33ccc80aa3870e016bef32b85e1.1623063174.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:10 +10:00
Christophe Leroy
45b30fafe5 powerpc: Define empty_zero_page[] in C
At the time being, empty_zero_page[] is defined in each
platform head.S.

Define it in mm/mem.c instead, and put it in BSS section instead
of the DATA section. Commit 5227cfa71f ("arm64: mm: place
empty_zero_page in bss") explains why it is interesting to have
it in BSS.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5838caffa269e0957c5a50cc85477876220298b0.1623063174.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:10 +10:00
Nicholas Piggin
e89a8ca94b powerpc/64s: Remove MSR[ISF] bit
No supported processor implements this mode. Setting the bit in
MSR values can be a bit confusing (and would prevent the bit from
ever being reused). Remove it.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201106045340.1935841-1-npiggin@gmail.com
2020-12-09 23:48:14 +11:00
Jordan Niethe
fe18a35e68 powerpc/64: Fix an EMIT_BUG_ENTRY in head_64.S
Commit 63ce271b5e ("powerpc/prom: convert PROM_BUG() to standard
trap") added an EMIT_BUG_ENTRY for the trap after the branch to
start_kernel(). The EMIT_BUG_ENTRY was for the address "0b", however the
trap was not labeled with "0". Hence the address used for bug is in
relative_toc() where the previous "0" label is. Label the trap as "0" so
the correct address is used.

Fixes: 63ce271b5e ("powerpc/prom: convert PROM_BUG() to standard trap")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201130004404.30953-1-jniethe5@gmail.com
2020-12-04 01:01:20 +11:00
Christophe Leroy
879add7720 powerpc/64s: Replace RFI by RFI_TO_KERNEL and remove RFI
In head_64.S, we have two places using RFI to return to
kernel. Use RFI_TO_KERNEL instead.

They are the two only places using RFI on book3s/64, so
the RFI macro can go away.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7719261b0a0d2787772339484c33eb809723bca7.1604854583.git.christophe.leroy@csgroup.eu
2020-11-19 16:56:54 +11:00
Jordan Niethe
3c0b976bf2 powerpc/64: Set up a kernel stack for secondaries before cpu_restore()
Currently in generic_secondary_smp_init(), cur_cpu_spec->cpu_restore()
is called before a stack has been set up in r1. This was previously fine
as the cpu_restore() functions were implemented in assembly and did not
use a stack. However commit 5a61ef74f2 ("powerpc/64s: Support new
device tree binding for discovering CPU features") used
__restore_cpu_cpufeatures() as the cpu_restore() function for a
device-tree features based cputable entry. This is a C function and
hence uses a stack in r1.

generic_secondary_smp_init() is entered on the secondary cpus via the
primary cpu using the OPAL call opal_start_cpu(). In OPAL, each hardware
thread has its own stack. The OPAL call is ran in the primary's hardware
thread. During the call, a job is scheduled on a secondary cpu that will
start executing at the address of generic_secondary_smp_init().  Hence
the value that will be left in r1 when the secondary cpu enters the
kernel is part of that secondary cpu's individual OPAL stack. This means
that __restore_cpu_cpufeatures() will write to that OPAL stack. This is
not horribly bad as each hardware thread has its own stack and the call
that enters the kernel from OPAL never returns, but it is still wrong
and should be corrected.

Create the temp kernel stack before calling cpu_restore().

As noted by mpe, for a kexec boot, the secondary CPUs are released from
the spin loop at address 0x60 by smp_release_cpus() and then jump to
generic_secondary_smp_init(). The call to smp_release_cpus() is in
setup_arch(), and it comes before the call to emergency_stack_init().
emergency_stack_init() allocates an emergency stack in the PACA for each
CPU.  This address in the PACA is what is used to set up the temp kernel
stack in generic_secondary_smp_init(). Move releasing the secondary CPUs
to after the PACAs have been allocated an emergency stack, otherwise the
PACA stack pointer will contain garbage and hence the temp kernel stack
created from it will be broken.

Fixes: 5a61ef74f2 ("powerpc/64s: Support new device tree binding for discovering CPU features")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201014072837.24539-1-jniethe5@gmail.com
2020-11-02 12:54:38 +11:00
Michael Ellerman
529d2bd56a powerpc/64: Remove unused generic_secondary_thread_init()
The last caller was removed in 2014 in commit fb5a515704 ("powerpc:
Remove platforms/wsp and associated pieces").

As Jordan noticed even though there are no callers, the code above in
fsl_secondary_thread_init() falls through into
generic_secondary_thread_init(). So we can remove the _GLOBAL but not
the body of the function.

However because fsl_secondary_thread_init() is inside #ifdef
CONFIG_PPC_BOOK3E, we can never reach the body of
generic_secondary_thread_init() unless CONFIG_PPC_BOOK3E is enabled,
so we can wrap the whole thing in a single #ifdef.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200819015704.1976364-1-mpe@ellerman.id.au
2020-09-08 22:24:17 +10:00
Michael Ellerman
7ffa8b7dc1 powerpc/64: Don't initialise init_task->thread.regs
Aneesh increased the size of struct pt_regs by 16 bytes and started
seeing this WARN_ON:

  smp: Bringing up secondary CPUs ...
  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 0 at arch/powerpc/kernel/process.c:455 giveup_all+0xb4/0x110
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc2-gcc-8.2.0-1.g8f6a41f-default+ #318
  NIP:  c00000000001a2b4 LR: c00000000001a29c CTR: c0000000031d0000
  REGS: c0000000026d3980 TRAP: 0700   Not tainted  (5.7.0-rc2-gcc-8.2.0-1.g8f6a41f-default+)
  MSR:  800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE>  CR: 48048224  XER: 00000000
  CFAR: c000000000019cc8 IRQMASK: 1
  GPR00: c00000000001a264 c0000000026d3c20 c0000000026d7200 800000000280b033
  GPR04: 0000000000000001 0000000000000000 0000000000000077 30206d7372203164
  GPR08: 0000000000002000 0000000002002000 800000000280b033 3230303030303030
  GPR12: 0000000000008800 c0000000031d0000 0000000000800050 0000000002000066
  GPR16: 000000000309a1a0 000000000309a4b0 000000000309a2d8 000000000309a890
  GPR20: 00000000030d0098 c00000000264da40 00000000fd620000 c0000000ff798080
  GPR24: c00000000264edf0 c0000001007469f0 00000000fd620000 c0000000020e5e90
  GPR28: c00000000264edf0 c00000000264d200 000000001db60000 c00000000264d200
  NIP [c00000000001a2b4] giveup_all+0xb4/0x110
  LR [c00000000001a29c] giveup_all+0x9c/0x110
  Call Trace:
  [c0000000026d3c20] [c00000000001a264] giveup_all+0x64/0x110 (unreliable)
  [c0000000026d3c90] [c00000000001ae34] __switch_to+0x104/0x480
  [c0000000026d3cf0] [c000000000e0b8a0] __schedule+0x320/0x970
  [c0000000026d3dd0] [c000000000e0c518] schedule_idle+0x38/0x70
  [c0000000026d3df0] [c00000000019c7c8] do_idle+0x248/0x3f0
  [c0000000026d3e70] [c00000000019cbb8] cpu_startup_entry+0x38/0x40
  [c0000000026d3ea0] [c000000000011bb0] rest_init+0xe0/0xf8
  [c0000000026d3ed0] [c000000002004820] start_kernel+0x990/0x9e0
  [c0000000026d3f90] [c00000000000c49c] start_here_common+0x1c/0x400

Which was unexpected. The warning is checking the thread.regs->msr
value of the task we are switching from:

  usermsr = tsk->thread.regs->msr;
  ...
  WARN_ON((usermsr & MSR_VSX) && !((usermsr & MSR_FP) && (usermsr & MSR_VEC)));

ie. if MSR_VSX is set then both of MSR_FP and MSR_VEC are also set.

Dumping tsk->thread.regs->msr we see that it's: 0x1db60000

Which is not a normal looking MSR, in fact the only valid bit is
MSR_VSX, all the other bits are reserved in the current definition of
the MSR.

We can see from the oops that it was swapper/0 that we were switching
from when we hit the warning, ie. init_task. So its thread.regs points
to the base (high addresses) in init_stack.

Dumping the content of init_task->thread.regs, with the members of
pt_regs annotated (the 16 bytes larger version), we see:

  0000000000000000 c000000002780080    gpr[0]     gpr[1]
  0000000000000000 c000000002666008    gpr[2]     gpr[3]
  c0000000026d3ed0 0000000000000078    gpr[4]     gpr[5]
  c000000000011b68 c000000002780080    gpr[6]     gpr[7]
  0000000000000000 0000000000000000    gpr[8]     gpr[9]
  c0000000026d3f90 0000800000002200    gpr[10]    gpr[11]
  c000000002004820 c0000000026d7200    gpr[12]    gpr[13]
  000000001db60000 c0000000010aabe8    gpr[14]    gpr[15]
  c0000000010aabe8 c0000000010aabe8    gpr[16]    gpr[17]
  c00000000294d598 0000000000000000    gpr[18]    gpr[19]
  0000000000000000 0000000000001ff8    gpr[20]    gpr[21]
  0000000000000000 c00000000206d608    gpr[22]    gpr[23]
  c00000000278e0cc 0000000000000000    gpr[24]    gpr[25]
  000000002fff0000 c000000000000000    gpr[26]    gpr[27]
  0000000002000000 0000000000000028    gpr[28]    gpr[29]
  000000001db60000 0000000004750000    gpr[30]    gpr[31]
  0000000002000000 000000001db60000    nip        msr
  0000000000000000 0000000000000000    orig_r3    ctr
  c00000000000c49c 0000000000000000    link       xer
  0000000000000000 0000000000000000    ccr        softe
  0000000000000000 0000000000000000    trap       dar
  0000000000000000 0000000000000000    dsisr      result
  0000000000000000 0000000000000000    ppr        kuap
  0000000000000000 0000000000000000    pad[2]     pad[3]

This looks suspiciously like stack frames, not a pt_regs. If we look
closely we can see return addresses from the stack trace above,
c000000002004820 (start_kernel) and c00000000000c49c (start_here_common).

init_task->thread.regs is setup at build time in processor.h:

  #define INIT_THREAD  { \
  	.ksp = INIT_SP, \
  	.regs = (struct pt_regs *)INIT_SP - 1, /* XXX bogus, I think */ \

The early boot code where we setup the initial stack is:

  LOAD_REG_ADDR(r3,init_thread_union)

  /* set up a stack pointer */
  LOAD_REG_IMMEDIATE(r1,THREAD_SIZE)
  add	r1,r3,r1
  li	r0,0
  stdu	r0,-STACK_FRAME_OVERHEAD(r1)

Which creates a stack frame of size 112 bytes (STACK_FRAME_OVERHEAD).
Which is far too small to contain a pt_regs.

So the result is init_task->thread.regs is pointing at some stack
frames on the init stack, not at a pt_regs.

We have gotten away with this for so long because with pt_regs at its
current size the MSR happens to point into the first frame, at a
location that is not written to by the early asm. With the 16 byte
expansion the MSR falls into the second frame, which is used by the
compiler, and collides with a saved register that tends to be
non-zero.

As far as I can see this has been wrong since the original merge of
64-bit ppc support, back in 2002.

Conceptually swapper should have no regs, it never entered from
userspace, and in fact that's what we do on 32-bit. It's also
presumably what the "bogus" comment is referring to.

So I think the right fix is to just not-initialise regs at all. I'm
slightly worried this will break some code that isn't prepared for a
NULL regs, but we'll have to see.

Remove the comment in head_64.S which refers to us setting up the
regs (even though we never did), and is otherwise not really accurate
any more.

Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200428123130.73078-1-mpe@ellerman.id.au
2020-05-15 11:58:54 +10:00
Michael Ellerman
6eeb9b3b9c powerpc/64s: Fix section mismatch warnings from boot code
We currently have two section mismatch warnings:

  The function __boot_from_prom() references
  the function __init prom_init().

  The function start_here_common() references
  the function __init start_kernel().

The warnings are correct, we do have branches from non-init code into
init code, which is freed after boot. But we don't expect to ever
execute any of that early boot code after boot, if we did that would
be a bug. In particular calling into OF after boot would be fatal
because OF is no longer resident.

So for now fix the warnings by marking the relevant functions as
__REF, which puts them in the ".ref.text" section.

This causes some reordering of the functions in the final link:

  @@ -217,10 +217,9 @@
   c00000000000b088 t generic_secondary_common_init
   c00000000000b124 t __mmu_off
   c00000000000b14c t __start_initialization_multiplatform
  -c00000000000b1ac t __boot_from_prom
  -c00000000000b1ec t __after_prom_start
  -c00000000000b260 t p_end
  -c00000000000b27c T copy_and_flush
  +c00000000000b1ac t __after_prom_start
  +c00000000000b220 t p_end
  +c00000000000b23c T copy_and_flush
   c00000000000b300 T __secondary_start
   c00000000000b300 t copy_to_here
   c00000000000b344 t start_secondary_prolog
  @@ -228,8 +227,9 @@
   c00000000000b36c t enable_64b_mode
   c00000000000b388 T relative_toc
   c00000000000b3a8 t p_toc
  -c00000000000b3b0 t start_here_common
  -c00000000000b3d0 t start_here_multiplatform
  +c00000000000b3b0 t __boot_from_prom
  +c00000000000b3f0 t start_here_multiplatform
  +c00000000000b480 t start_here_common
   c00000000000b880 T system_call_common
   c00000000000b974 t system_call
   c00000000000b9dc t system_call_exit

In particular __boot_from_prom moves after copy_to_here, which means
it's not copied to zero in the first stage of copy of the kernel to
zero.

But that's OK, because we only call __boot_from_prom before we do the
copy, so it makes no difference when it's copied. The call sequence
is:
  __start
  -> __start_initialization_multiplatform
     -> __boot_from_prom
        -> __start
           -> __start_initialization_multiplatform
              -> __after_prom_start
                 -> copy_and_flush
                 -> copy_and_flush (relocated to 0)
                    -> start_here_multiplatform
                       -> early_setup

Reported-by: Mauricio Faria de Oliveira <mauricfo@linux.ibm.com>
Reported-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200225031328.14676-1-mpe@ellerman.id.au
2020-03-25 12:07:59 +11:00
Christophe Leroy
63ce271b5e powerpc/prom: convert PROM_BUG() to standard trap
Prior to commit 1bd98d7fbaf5 ("ppc64: Update BUG handling based on
ppc32"), BUG() family was using BUG_ILLEGAL_INSTRUCTION which
was an invalid instruction opcode to trap into program check
exception.

That commit converted them to using standard trap instructions,
but prom/prom_init and their PROM_BUG() macro were left over.
head_64.S and exception-64s.S were left aside as well.

Convert them to using the standard BUG infrastructure.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/cdaf4bbbb64c288a077845846f04b12683f8875a.1566817807.git.christophe.leroy@c-s.fr
2019-08-28 11:31:18 +10:00
Christophe Leroy
d7fb5b18a5 powerpc/64: optimise LOAD_REG_IMMEDIATE_SYM()
Optimise LOAD_REG_IMMEDIATE_SYM() using a temporary register to
parallelise operations.

It reduces the path from 5 to 3 instructions.

Suggested-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/bad41ed02531bb0382420cbab50a0d7153b71767.1566311636.git.christophe.leroy@c-s.fr
2019-08-27 13:03:36 +10:00
Christophe Leroy
c691b4b83b powerpc: rewrite LOAD_REG_IMMEDIATE() as an intelligent macro
Today LOAD_REG_IMMEDIATE() is a basic #define which loads all
parts on a value into a register, including the parts that are NUL.

This means always 2 instructions on PPC32 and always 5 instructions
on PPC64. And those instructions cannot run in parallele as they are
updating the same register.

Ex: LOAD_REG_IMMEDIATE(r1,THREAD_SIZE) in head_64.S results in:

3c 20 00 00     lis     r1,0
60 21 00 00     ori     r1,r1,0
78 21 07 c6     rldicr  r1,r1,32,31
64 21 00 00     oris    r1,r1,0
60 21 40 00     ori     r1,r1,16384

Rewrite LOAD_REG_IMMEDIATE() with GAS macro in order to skip
the parts that are NUL.

Rename existing LOAD_REG_IMMEDIATE() as LOAD_REG_IMMEDIATE_SYM()
and use that one for loading value of symbols which are not known
at compile time.

Now LOAD_REG_IMMEDIATE(r1,THREAD_SIZE) in head_64.S results in:

38 20 40 00     li      r1,16384

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d60ce8dd3a383c7adbfc322bf1d53d81724a6000.1566311636.git.christophe.leroy@c-s.fr
2019-08-27 13:03:36 +10:00
Linus Torvalds
192f0f8e9d powerpc updates for 5.3
Notable changes:
 
  - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver, as well
    as some other functions only used by drivers that haven't (yet?) made it
    upstream.
 
  - A fix for a bug in our handling of hardware watchpoints (eg. perf record -e
    mem: ...) which could lead to register corruption and kernel crashes.
 
  - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for vmalloc
    when using the Radix MMU.
 
  - A large but incremental rewrite of our exception handling code to use gas
    macros rather than multiple levels of nested CPP macros.
 
 And the usual small fixes, cleanups and improvements.
 
 Thanks to:
   Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju
   T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Cédric Le Goater,
   Christian Lamparter, Christophe Leroy, Christophe Lombard, Christoph Hellwig,
   Daniel Axtens, Denis Efremov, Enrico Weigelt, Frederic Barrat, Gautham R.
   Shenoy, Geert Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg
   Kurz, Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
   Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N. Rao,
   Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi Bangoria,
   Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher Boessenkool, Shaokun
   Zhang, Shawn Anastasio, Stewart Smith, Suraj Jitindar Singh, Thiago Jung
   Bauermann, YueHaibing.
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Merge tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver,
     as well as some other functions only used by drivers that haven't
     (yet?) made it upstream.

   - A fix for a bug in our handling of hardware watchpoints (eg. perf
     record -e mem: ...) which could lead to register corruption and
     kernel crashes.

   - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for
     vmalloc when using the Radix MMU.

   - A large but incremental rewrite of our exception handling code to
     use gas macros rather than multiple levels of nested CPP macros.

  And the usual small fixes, cleanups and improvements.

  Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab,
  Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann,
  Athira Rajeev, Cédric Le Goater, Christian Lamparter, Christophe
  Leroy, Christophe Lombard, Christoph Hellwig, Daniel Axtens, Denis
  Efremov, Enrico Weigelt, Frederic Barrat, Gautham R. Shenoy, Geert
  Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg Kurz,
  Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
  Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N.
  Rao, Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi
  Bangoria, Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher
  Boessenkool, Shaokun Zhang, Shawn Anastasio, Stewart Smith, Suraj
  Jitindar Singh, Thiago Jung Bauermann, YueHaibing"

* tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (163 commits)
  powerpc/powernv/idle: Fix restore of SPRN_LDBAR for POWER9 stop state.
  powerpc/eeh: Handle hugepages in ioremap space
  ocxl: Update for AFU descriptor template version 1.1
  powerpc/boot: pass CONFIG options in a simpler and more robust way
  powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h
  powerpc/irq: Don't WARN continuously in arch_local_irq_restore()
  powerpc/module64: Use symbolic instructions names.
  powerpc/module32: Use symbolic instructions names.
  powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h
  powerpc/module64: Fix comment in R_PPC64_ENTRY handling
  powerpc/boot: Add lzo support for uImage
  powerpc/boot: Add lzma support for uImage
  powerpc/boot: don't force gzipped uImage
  powerpc/8xx: Add microcode patch to move SMC parameter RAM.
  powerpc/8xx: Use IO accessors in microcode programming.
  powerpc/8xx: replace #ifdefs by IS_ENABLED() in microcode.c
  powerpc/8xx: refactor programming of microcode CPM params.
  powerpc/8xx: refactor printing of microcode patch name.
  powerpc/8xx: Refactor microcode write
  powerpc/8xx: refactor writing of CPM microcode arrays
  ...
2019-07-13 16:08:36 -07:00
Christophe Leroy
9c4e4c90ec powerpc/64: mark start_here_multiplatform as __ref
Otherwise, the following warning is encountered:

WARNING: vmlinux.o(.text+0x3dc6): Section mismatch in reference from the variable start_here_multiplatform to the function .init.text:.early_setup()
The function start_here_multiplatform() references
the function __init .early_setup().
This is often because start_here_multiplatform lacks a __init
annotation or the annotation of .early_setup is wrong.

Fixes: 56c46bba9b ("powerpc/64: Fix booting large kernels with STRICT_KERNEL_RWX")
Cc: Russell Currey <ruscur@russell.cc>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-06-16 00:00:30 +10:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
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 <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Russell Currey
56c46bba9b powerpc/64: Fix booting large kernels with STRICT_KERNEL_RWX
With STRICT_KERNEL_RWX enabled anything marked __init is placed at a 16M
boundary.  This is necessary so that it can be repurposed later with
different permissions.  However, in kernels with text larger than 16M,
this pushes early_setup past 32M, incapable of being reached by the
branch instruction.

Fix this by setting the CTR and branching there instead.

Fixes: 1e0fc9d1eb ("powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs")
Signed-off-by: Russell Currey <ruscur@russell.cc>
[mpe: Fix it to work on BE by using DOTSYM()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-20 22:02:12 +10:00
Michael Ellerman
eafd825ed7 powerpc/64: Simplify __secondary_start paca->kstack handling
In __secondary_start() we load the thread_info of the idle task of the
secondary CPU from current_set[cpu], and then convert it into a stack
pointer before storing that back to paca->kstack.

As pointed out in commit f761622e59 ("powerpc: Initialise
paca->kstack before early_setup_secondary") it's important that we
initialise paca->kstack before calling the MMU setup code, in
particular slb_initialize(), because it will bolt the SLB entry for
the kstack into the SLB.

However we have already setup paca->kstack in cpu_idle_thread_init(),
since commit 3b5750644b ("[POWERPC] Bolt in SLB entry for kernel
stack on secondary cpus") (May 2008).

It's also in cpu_idle_thread_init() that we initialise current_set[cpu]
with the thread_info pointer, so there is no issue of the timing being
different between the two.

Therefore the initialisation of paca->kstack in __setup_secondary() is
completely redundant, so remove it.

This has the added benefit of removing code that runs in real mode,
and is therefore restricted by the RMO, and so opens the way for us to
enable THREAD_INFO_IN_TASK.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:39 +11:00
Christophe Leroy
2c86cd188f powerpc: clean inclusions of asm/feature-fixups.h
files not using feature fixup don't need asm/feature-fixups.h
files using feature fixup need asm/feature-fixups.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-30 22:48:17 +10:00
Nicholas Piggin
d2e60075a3 powerpc/64: Use array of paca pointers and allocate pacas individually
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 <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:23 +11:00
Madhavan Srinivasan
4e26bc4a4e powerpc/64: Rename soft_enabled to irq_soft_mask
Rename the paca->soft_enabled to paca->irq_soft_mask as it is no
longer used as a flag for interrupt state, but a mask.

Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:37:01 +11:00
Madhavan Srinivasan
c2e480ba82 powerpc/64: Add #defines for paca->soft_enabled flags
Two #defines IRQS_ENABLED and IRQS_DISABLED are added to be used when
updating paca->soft_enabled. Replace the hardcoded values used when
updating paca->soft_enabled with IRQ_(EN|DIS)ABLED #define. No logic
change.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:56 +11:00
Nicholas Piggin
339a3293f4 powerpc/powernv: Avoid waiting for secondary hold spinloop with OPAL
OPAL boot does not insert secondaries at 0x60 to wait at the secondary
hold spinloop. Instead they are started later, and inserted at
generic_secondary_smp_init(), which is after the secondary hold
spinloop.

Avoid waiting on this spinloop when booting with OPAL firmware. This
wait always times out that case.

This saves 100ms boot time on powernv, and 10s of seconds of real time
when booting on the simulator in SMP.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10 22:00:54 +11:00
Tobin C. Harding
eb039161da powerpc/asm: Convert .llong directives to .8byte
.llong is an undocumented PPC specific directive. The generic
equivalent is .quad, but even better (because it's self describing) is
.8byte.

Convert all .llong directives to .8byte.

Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:47 +10:00
Hamish Martin
cabed14891 powerpc/64: Allow for THREAD_SIZE > 16k
Fix an assembler error when the THREAD_SIZE is greater than 16k.

Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-20 19:02:49 +11:00