[PATCH v14 00/12] powerpc: Switch to CONFIG_THREAD_INFO_IN_TASK

[Christophe Leroy]

The purpose of this serie is to activate 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.

Added Mark Rutland in copy as he did the work on arm64 and may have recommendations for us.

Changes in v14 (ie since v13):
 - Added in front a fixup patch which conflicts with this serie
 - Added a patch for using try_get_task_stack()/put_task_stack() in stack walkers.
 - Fixed compilation failure in the preparation patch (by moving the modification
 of klp_init_thread_info() to the following patch)

Changes since v12:
 - Patch 1: Taken comment from Mike (re-introduced the 'panic' in case memblock allocation fails in setup_64.c
 - Patch 1: Added alloc_stack() function in setup_32.c to also panic in case of allocation failure.

Changes since v11:
 - Rebased on 81775f5563fa ("Automatic merge of branches 'master', 'next' and 'fixes' into merge")
 - Added a first patch to change memblock allocs to functions returning virtual addrs. This removes
   the memset() which were the only remaining stuff in irq_ctx_init() and exc_lvl_ctx_init() at the end.
 - dropping irq_ctx_init() and exc_lvl_ctx_init() in patch 5 (powerpc: Activate CONFIG_THREAD_INFO_IN_TASK)
 - A few cosmetic changes in commit log and code.

Changes since v10:
 - Rebased on 21622a0d2023 ("Automatic merge of branches 'master', 'next' and 'fixes' into merge")
  ==> Fixed conflict in setup_32.S

Changes since v9:
 - Rebased on 183cbf93be88 ("Automatic merge of branches 'master', 'next' and 'fixes' into merge")
  ==> Fixed conflict on xmon

Changes since v8:
 - Rebased on e589b79e40d9 ("Automatic merge of branches 'master', 'next' and 'fixes' into merge")
  ==> Main impact was conflicts due to commit 9a8dd708d547 ("memblock: rename memblock_alloc{_nid,_try_nid} to memblock_phys_alloc*")

Changes since v7:
 - Rebased on fb6c6ce7907d ("Automatic merge of branches 'master', 'next' and 'fixes' into merge")

Changes since v6:
 - Fixed validate_sp() to exclude NULL sp in 'regain entire stack space' patch (early crash with CONFIG_KMEMLEAK)

Changes since v5:
 - Fixed livepatch_sp setup by using end_of_stack() instead of hardcoding
 - Fixed PPC_BPF_LOAD_CPU() macro

Changes since v4:
 - Fixed a build failure on 32bits SMP when include/generated/asm-offsets.h is not
 already existing, was due to spaces instead of a tab in the Makefile

Changes since RFC v3: (based on Nick's review)
 - Renamed task_size.h to task_size_user64.h to better relate to what it contains.
 - Handling of the isolation of thread_info cpu field inside CONFIG_SMP #ifdefs moved to a separate patch.
 - Removed CURRENT_THREAD_INFO macro completely.
 - Added a guard in asm/smp.h to avoid build failure before _TASK_CPU is defined.
 - Added a patch at the end to rename 'tp' pointers to 'sp' pointers
 - Renamed 'tp' into 'sp' pointers in preparation patch when relevant
 - Fixed a few commit logs
 - Fixed checkpatch report.

Changes since RFC v2:
 - Removed the modification of names in asm-offsets
 - Created a rule in arch/powerpc/Makefile to append the offset of current->cpu in CFLAGS
 - Modified asm/smp.h to use the offset set in CFLAGS
 - Squashed the renaming of THREAD_INFO to TASK_STACK in the preparation patch
 - Moved the modification of current_pt_regs in the patch activating CONFIG_THREAD_INFO_IN_TASK

Changes since RFC v1:
 - Removed the first patch which was modifying header inclusion order in timer
 - Modified some names in asm-offsets to avoid conflicts when including asm-offsets in C files
 - Modified asm/smp.h to avoid having to include linux/sched.h (using asm-offsets instead)
 - Moved some changes from the activation patch to the preparation patch.

Christophe Leroy (12):
  powerpc/32: Fix CONFIG_VIRT_CPU_ACCOUNTING_NATIVE for 40x/booke
  powerpc/irq: use memblock functions returning virtual address
  book3s/64: avoid circular header inclusion in mmu-hash.h
  powerpc: Only use task_struct 'cpu' field on SMP
  powerpc: prep stack walkers for THREAD_INFO_IN_TASK
  powerpc: Prepare for moving thread_info into task_struct
  powerpc: Activate CONFIG_THREAD_INFO_IN_TASK
  powerpc: regain entire stack space
  powerpc: 'current_set' is now a table of task_struct pointers
  powerpc/32: Remove CURRENT_THREAD_INFO and rename TI_CPU
  powerpc/64: Remove CURRENT_THREAD_INFO
  powerpc: clean stack pointers naming

 arch/powerpc/Kconfig                           |   1 +
 arch/powerpc/Makefile                          |   7 ++
 arch/powerpc/include/asm/asm-prototypes.h      |   4 +-
 arch/powerpc/include/asm/book3s/64/mmu-hash.h  |   2 +-
 arch/powerpc/include/asm/exception-64s.h       |   4 +-
 arch/powerpc/include/asm/irq.h                 |  18 ++--
 arch/powerpc/include/asm/livepatch.h           |   6 +-
 arch/powerpc/include/asm/processor.h           |  39 +--------
 arch/powerpc/include/asm/ptrace.h              |   2 +-
 arch/powerpc/include/asm/reg.h                 |   2 +-
 arch/powerpc/include/asm/smp.h                 |  17 +++-
 arch/powerpc/include/asm/task_size_user64.h    |  42 +++++++++
 arch/powerpc/include/asm/thread_info.h         |  19 -----
 arch/powerpc/kernel/asm-offsets.c              |  10 ++-
 arch/powerpc/kernel/entry_32.S                 |  75 ++++++----------
 arch/powerpc/kernel/entry_64.S                 |  12 +--
 arch/powerpc/kernel/epapr_hcalls.S             |   5 +-
 arch/powerpc/kernel/exceptions-64e.S           |  13 +--
 arch/powerpc/kernel/exceptions-64s.S           |   2 +-
 arch/powerpc/kernel/head_32.S                  |  14 +--
 arch/powerpc/kernel/head_40x.S                 |   4 +-
 arch/powerpc/kernel/head_44x.S                 |   8 +-
 arch/powerpc/kernel/head_64.S                  |   1 +
 arch/powerpc/kernel/head_8xx.S                 |   2 +-
 arch/powerpc/kernel/head_booke.h               |  12 +--
 arch/powerpc/kernel/head_fsl_booke.S           |  16 ++--
 arch/powerpc/kernel/idle_6xx.S                 |   8 +-
 arch/powerpc/kernel/idle_book3e.S              |   2 +-
 arch/powerpc/kernel/idle_e500.S                |   8 +-
 arch/powerpc/kernel/idle_power4.S              |   2 +-
 arch/powerpc/kernel/irq.c                      | 114 +++----------------------
 arch/powerpc/kernel/kgdb.c                     |  28 ------
 arch/powerpc/kernel/machine_kexec_64.c         |   6 +-
 arch/powerpc/kernel/misc_32.S                  |  17 ++--
 arch/powerpc/kernel/process.c                  |  63 ++++++++------
 arch/powerpc/kernel/setup-common.c             |   2 +-
 arch/powerpc/kernel/setup_32.c                 |  25 +++---
 arch/powerpc/kernel/setup_64.c                 |  51 +++--------
 arch/powerpc/kernel/smp.c                      |  16 ++--
 arch/powerpc/kernel/stacktrace.c               |  29 ++++++-
 arch/powerpc/kernel/trace/ftrace_64_mprofile.S |   6 +-
 arch/powerpc/kvm/book3s_hv_hmi.c               |   1 +
 arch/powerpc/mm/hash_low_32.S                  |  14 ++-
 arch/powerpc/net/bpf_jit32.h                   |   5 +-
 arch/powerpc/sysdev/6xx-suspend.S              |   5 +-
 arch/powerpc/xmon/xmon.c                       |   2 +-
 46 files changed, 300 insertions(+), 441 deletions(-)
 create mode 100644 arch/powerpc/include/asm/task_size_user64.h

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2.13.3