linux.git/arch/powerpc/kernel, branch v6.5

powerpc/rtas_flash: allow user copy to flash block cache objects

2023-08-16T23:46:14+00:00

With hardened usercopy enabled (CONFIG_HARDENED_USERCOPY=y), using the
/proc/powerpc/rtas/firmware_update interface to prepare a system
firmware update yields a BUG():

  kernel BUG at mm/usercopy.c:102!
  Oops: Exception in kernel mode, sig: 5 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in:
  CPU: 0 PID: 2232 Comm: dd Not tainted 6.5.0-rc3+ #2
  Hardware name: IBM,8408-E8E POWER8E (raw) 0x4b0201 0xf000004 of:IBM,FW860.50 (SV860_146) hv:phyp pSeries
  NIP:  c0000000005991d0 LR: c0000000005991cc CTR: 0000000000000000
  REGS: c0000000148c76a0 TRAP: 0700   Not tainted  (6.5.0-rc3+)
  MSR:  8000000000029033   CR: 24002242  XER: 0000000c
  CFAR: c0000000001fbd34 IRQMASK: 0
  [ ... GPRs omitted ... ]
  NIP usercopy_abort+0xa0/0xb0
  LR  usercopy_abort+0x9c/0xb0
  Call Trace:
    usercopy_abort+0x9c/0xb0 (unreliable)
    __check_heap_object+0x1b4/0x1d0
    __check_object_size+0x2d0/0x380
    rtas_flash_write+0xe4/0x250
    proc_reg_write+0xfc/0x160
    vfs_write+0xfc/0x4e0
    ksys_write+0x90/0x160
    system_call_exception+0x178/0x320
    system_call_common+0x160/0x2c4

The blocks of the firmware image are copied directly from user memory
to objects allocated from flash_block_cache, so flash_block_cache must
be created using kmem_cache_create_usercopy() to mark it safe for user
access.

Fixes: 6d07d1cd300f ("usercopy: Restrict non-usercopy caches to size 0")
Signed-off-by: Nathan Lynch 
Reviewed-by: Kees Cook 
[mpe: Trim and indent oops]
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230810-rtas-flash-vs-hardened-usercopy-v2-1-dcf63793a938@linux.ibm.com

powerpc/64e: Fix secondary thread bringup for ELFv2 kernels

2023-08-01T11:01:27+00:00

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: 8c5fa3b5c4df ("powerpc/64: Make ELFv2 the default for big-endian builds")
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230801102650.48705-1-mpe@ellerman.id.au

powerpc/ftrace: Create a dummy stackframe to fix stack unwind

2023-07-28T10:23:57+00:00

With ppc64 -mprofile-kernel and ppc32 -pg, profiling instructions to
call into ftrace are emitted right at function entry. The instruction
sequence used is minimal to reduce overhead. Crucially, a stackframe is
not created for the function being traced. This breaks stack unwinding
since the function being traced does not have a stackframe for itself.
As such, it never shows up in the backtrace:

/sys/kernel/debug/tracing # echo 1 > /proc/sys/kernel/stack_tracer_enabled
/sys/kernel/debug/tracing # cat stack_trace
        Depth    Size   Location    (17 entries)
        -----    ----   --------
  0)     4144      32   ftrace_call+0x4/0x44
  1)     4112     432   get_page_from_freelist+0x26c/0x1ad0
  2)     3680     496   __alloc_pages+0x290/0x1280
  3)     3184     336   __folio_alloc+0x34/0x90
  4)     2848     176   vma_alloc_folio+0xd8/0x540
  5)     2672     272   __handle_mm_fault+0x700/0x1cc0
  6)     2400     208   handle_mm_fault+0xf0/0x3f0
  7)     2192      80   ___do_page_fault+0x3e4/0xbe0
  8)     2112     160   do_page_fault+0x30/0xc0
  9)     1952     256   data_access_common_virt+0x210/0x220
 10)     1696     400   0xc00000000f16b100
 11)     1296     384   load_elf_binary+0x804/0x1b80
 12)      912     208   bprm_execve+0x2d8/0x7e0
 13)      704      64   do_execveat_common+0x1d0/0x2f0
 14)      640     160   sys_execve+0x54/0x70
 15)      480      64   system_call_exception+0x138/0x350
 16)      416     416   system_call_common+0x160/0x2c4

Fix this by having ftrace create a dummy stackframe for the function
being traced. With this, backtraces now capture the function being
traced:

/sys/kernel/debug/tracing # cat stack_trace
        Depth    Size   Location    (17 entries)
        -----    ----   --------
  0)     3888      32   _raw_spin_trylock+0x8/0x70
  1)     3856     576   get_page_from_freelist+0x26c/0x1ad0
  2)     3280      64   __alloc_pages+0x290/0x1280
  3)     3216     336   __folio_alloc+0x34/0x90
  4)     2880     176   vma_alloc_folio+0xd8/0x540
  5)     2704     416   __handle_mm_fault+0x700/0x1cc0
  6)     2288      96   handle_mm_fault+0xf0/0x3f0
  7)     2192      48   ___do_page_fault+0x3e4/0xbe0
  8)     2144     192   do_page_fault+0x30/0xc0
  9)     1952     608   data_access_common_virt+0x210/0x220
 10)     1344      16   0xc0000000334bbb50
 11)     1328     416   load_elf_binary+0x804/0x1b80
 12)      912      64   bprm_execve+0x2d8/0x7e0
 13)      848     176   do_execveat_common+0x1d0/0x2f0
 14)      672     192   sys_execve+0x54/0x70
 15)      480      64   system_call_exception+0x138/0x350
 16)      416     416   system_call_common+0x160/0x2c4

This results in two additional stores in the ftrace entry code, but
produces reliable backtraces.

Fixes: 153086644fd1 ("powerpc/ftrace: Add support for -mprofile-kernel ftrace ABI")
Cc: stable@vger.kernel.org
Signed-off-by: Naveen N Rao 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230621051349.759567-1-naveen@kernel.org

Revert "powerpc/bug: Provide better flexibility to WARN_ON/__WARN_FLAGS() with asm goto"

2023-07-17T00:35:28+00:00

This partly reverts commit 1e688dd2a3d6759d416616ff07afc4bb836c4213.

That commit aimed at optimising the code around generation of
WARN_ON/BUG_ON but this leads to a lot of dead code erroneously
generated by GCC.

That dead code becomes a problem when we start using objtool validation
because objtool will abort validation with a warning as soon as it
detects unreachable code. This is because unreachable code might
be the indication that objtool doesn't properly decode object text.

     text	   data	    bss	    dec	    hex	filename
  9551585	3627834	 224376	13403795	 cc8693	vmlinux.before
  9535281	3628358	 224376	13388015	 cc48ef	vmlinux.after

Once this change is reverted, in a standard configuration (pmac32 +
function tracer) the text is reduced by 16k which is around 1.7%

We already had problem with it when starting to use objtool on powerpc
as a replacement for recordmcount, see commit 93e3f45a2631 ("powerpc:
Fix __WARN_FLAGS() for use with Objtool")

There is also a problem with at least GCC 12, on ppc64_defconfig +
CONFIG_CC_OPTIMIZE_FOR_SIZE=y + CONFIG_DEBUG_SECTION_MISMATCH=y :

    LD      .tmp_vmlinux.kallsyms1
  powerpc64-linux-ld: net/ipv4/tcp_input.o:(__ex_table+0xc4): undefined reference to `.L2136'
  make[2]: *** [scripts/Makefile.vmlinux:36: vmlinux] Error 1
  make[1]: *** [/home/chleroy/linux-powerpc/Makefile:1238: vmlinux] Error 2

Taking into account that other problems are encountered with that
'asm goto' in WARN_ON(), including build failures, keeping that
change is not worth it allthough it is primarily a compiler bug.

Revert it for now.

mpe: Retain EMIT_WARN_ENTRY as a synonym for EMIT_BUG_ENTRY to reduce
churn, as there are now nearly as many uses of EMIT_WARN_ENTRY as
EMIT_BUG_ENTRY.

Signed-off-by: Christophe Leroy 
Acked-by: Naveen N Rao 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230712134552.534955-1-mpe@ellerman.id.au

powerpc/64e: Fix obtool warnings in exceptions-64e.S

2023-07-09T23:47:47+00:00

Since commit aec0ba7472a7 ("powerpc/64: Use -mprofile-kernel for big
endian ELFv2 kernels"), this file is checked by objtool. Fix warnings
such as:

  arch/powerpc/kernel/idle_64e.o: warning: objtool: .text+0x20: unannotated intra-function call
  arch/powerpc/kernel/exceptions-64e.o: warning: objtool: .text+0x218: unannotated intra-function call

Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230622112451.735268-1-mpe@ellerman.id.au

powerpc/security: Fix Speculation_Store_Bypass reporting on Power10

2023-07-09T23:47:47+00:00

Nageswara reported that /proc/self/status was showing "vulnerable" for
the Speculation_Store_Bypass feature on Power10, eg:

  $ grep Speculation_Store_Bypass: /proc/self/status
  Speculation_Store_Bypass:       vulnerable

But at the same time the sysfs files, and lscpu, were showing "Not
affected".

This turns out to simply be a bug in the reporting of the
Speculation_Store_Bypass, aka. PR_SPEC_STORE_BYPASS, case.

When SEC_FTR_STF_BARRIER was added, so that firmware could communicate
the vulnerability was not present, the code in ssb_prctl_get() was not
updated to check the new flag.

So add the check for SEC_FTR_STF_BARRIER being disabled. Rather than
adding the new check to the existing if block and expanding the comment
to cover both cases, rewrite the three cases to be separate so they can
be commented separately for clarity.

Fixes: 84ed26fd00c5 ("powerpc/security: Add a security feature for STF barrier")
Cc: stable@vger.kernel.org # v5.14+
Reported-by: Nageswara R Sastry 
Tested-by: Nageswara R Sastry 
Reviewed-by: Russell Currey 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20230517074945.53188-1-mpe@ellerman.id.au

Merge tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2023-07-03T20:14:58+00:00

Pull tty/serial driver updates from Greg KH:
 "Here is the big set of tty/serial driver updates for 6.5-rc1.

  Included in here are:

   - tty_audit code cleanups from Jiri

   - more 8250 cleanups from Ilpo

   - samsung_tty driver bugfixes

   - 8250 lock port updates

   - usual fsl_lpuart driver updates and fixes

   - other small serial driver fixes and updates, full details in the
     shortlog

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (58 commits)
  tty_audit: make data of tty_audit_log() const
  tty_audit: make tty pointers in exposed functions const
  tty_audit: make icanon a bool
  tty_audit: invert the condition in tty_audit_log()
  tty_audit: use kzalloc() in tty_audit_buf_alloc()
  tty_audit: use TASK_COMM_LEN for task comm
  Revert "8250: add support for ASIX devices with a FIFO bug"
  serial: atmel: don't enable IRQs prematurely
  tty: serial: Add Nuvoton ma35d1 serial driver support
  tty: serial: fsl_lpuart: add earlycon for imx8ulp platform
  tty: serial: imx: fix rs485 rx after tx
  selftests: tty: add selftest for tty timestamp updates
  tty: tty_io: update timestamps on all device nodes
  tty: fix hang on tty device with no_room set
  serial: core: fix -EPROBE_DEFER handling in init
  serial: 8250_omap: Use force_suspend and resume for system suspend
  tty: serial: samsung_tty: Use abs() to simplify some code
  tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() when iterating clk
  tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() in case of error
  serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE
  ...

Merge tag 'kbuild-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2023-07-01T16:24:31+00:00

Pull Kbuild updates from Masahiro Yamada:

 - Remove the deprecated rule to build *.dtbo from *.dts

 - Refactor section mismatch detection in modpost

 - Fix bogus ARM section mismatch detections

 - Fix error of 'make gtags' with O= option

 - Add Clang's target triple to KBUILD_CPPFLAGS to fix a build error
   with the latest LLVM version

 - Rebuild the built-in initrd when KBUILD_BUILD_TIMESTAMP is changed

 - Ignore more compiler-generated symbols for kallsyms

 - Fix 'make local*config' to handle the ${CONFIG_FOO} form in Makefiles

 - Enable more kernel-doc warnings with W=2

 - Refactor  by generating KSYMTAB data by modpost

 - Deprecate  and 

 - Remove the EXPORT_DATA_SYMBOL macro

 - Move the check for static EXPORT_SYMBOL back to modpost, which makes
   the build faster

 - Re-implement CONFIG_TRIM_UNUSED_KSYMS with one-pass algorithm

 - Warn missing MODULE_DESCRIPTION when building modules with W=1

 - Make 'make clean' robust against too long argument error

 - Exclude more objects from GCOV to fix CFI failures with GCOV

 - Allow 'make modules_install' to install modules.builtin and
   modules.builtin.modinfo even when CONFIG_MODULES is disabled

 - Include modules.builtin and modules.builtin.modinfo in the
   linux-image Debian package even when CONFIG_MODULES is disabled

 - Revive "Entering directory" logging for the latest Make version

* tag 'kbuild-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (72 commits)
  modpost: define more R_ARM_* for old distributions
  kbuild: revive "Entering directory" for Make >= 4.4.1
  kbuild: set correct abs_srctree and abs_objtree for package builds
  scripts/mksysmap: Ignore prefixed KCFI symbols
  kbuild: deb-pkg: remove the CONFIG_MODULES check in buildeb
  kbuild: builddeb: always make modules_install, to install modules.builtin*
  modpost: continue even with unknown relocation type
  modpost: factor out Elf_Sym pointer calculation to section_rel()
  modpost: factor out inst location calculation to section_rel()
  kbuild: Disable GCOV for *.mod.o
  kbuild: Fix CFI failures with GCOV
  kbuild: make clean rule robust against too long argument error
  script: modpost: emit a warning when the description is missing
  kbuild: make modules_install copy modules.builtin(.modinfo)
  linux/export.h: rename 'sec' argument to 'license'
  modpost: show offset from symbol for section mismatch warnings
  modpost: merge two similar section mismatch warnings
  kbuild: implement CONFIG_TRIM_UNUSED_KSYMS without recursion
  modpost: use null string instead of NULL pointer for default namespace
  modpost: squash sym_update_namespace() into sym_add_exported()
  ...

Merge tag 'pci-v6.5-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

2023-06-30T22:06:45+00:00

Pull pci updates from Bjorn Helgaas:
 "Enumeration:

   - Export pcie_retrain_link() for use outside ASPM

   - Add Data Link Layer Link Active Reporting as another way for
     pcie_retrain_link() to determine the link is up

   - Work around link training failures (especially on the ASMedia
     ASM2824 switch) by training first at 2.5GT/s and then attempting
     higher rates

  Resource management:

   - When we coalesce host bridge windows, remove invalidated resources
     from the resource tree so future allocations work correctly

  Hotplug:

   - Cancel bringup sequence if card is not present, to keep from
     blinking Power Indicator indefinitely

   - Reassign bridge resources if necessary for ACPI hotplug

  Driver binding:

   - Convert platform_device .remove() callbacks to return void instead
     of a mostly useless int

  Power management:

   - Reduce wait time for secondary bus to be ready to speed up resume

   - Avoid putting EloPOS E2/S2/H2 (as well as Elo i2) PCIe Ports in
     D3cold

   - Call _REG when transitioning D-states so AML that uses the PCI
     config space OpRegion works, which fixes some ASMedia GPIO
     controllers after resume

  Virtualization:

   - Delay extra 250ms after FLR of Solidigm P44 Pro NVMe to avoid KVM
     hang when guest is rebooted

   - Add function 1 DMA alias quirk for Marvell 88SE9235

  Error handling:

   - Unexport pci_save_aer_state() since it's only used in drivers/pci/

   - Drop recommendation for drivers to configure AER Capability, since
     the PCI core does this for all devices

  ASPM:

   - Disable ASPM on MFD function removal to avoid use-after-free

   - Tighten up pci_enable_link_state() and pci_disable_link_state()
     interfaces so they don't enable/disable states the driver didn't
     specify

   - Avoid link retraining race that can happen if ASPM sets link
     control parameters while the link is in the midst of training for
     some other reason

  Endpoint framework:

   - Change "PCI Endpoint Virtual NTB driver" Kconfig prompt to be
     different from "PCI Endpoint NTB driver"

   - Automatically create a function specific attributes group for
     endpoint drivers to avoid reference counting issues

   - Fix many EPC test issues

   - Return pci_epf_type_add_cfs() error if EPF has no driver

   - Add kernel-doc for pci_epc_raise_irq() and pci_epc_map_msi_irq()
     MSI vector parameters

   - Pass EPF device ID to driver probe functions

   - Return -EALREADY if EPC has already been started/stopped

   - Add linkdown notifier support and use it in qcom-ep

   - Add Bus Master Enable event support and use it in qcom-ep

   - Add Qualcomm Modem Host Interface (MHI) endpoint driver

   - Add Layerscape PME interrupt handling to manage link-up
     notification

  Cadence PCIe controller driver:

   - Wait for link retrain to complete when working around the J721E
     i2085 erratum with Gen2 mode

  Faraday FTPC100 PCI controller driver:

   - Release clock resources on error paths

  Freescale i.MX6 PCIe controller driver:

   - Save and restore Root Port MSI control to work around hardware defect

  Intel VMD host bridge driver:

   - Reset VMD config register between soft reboots

   - Capture pci_reset_bus() return value instead of printing junk when
     it fails

  Qualcomm PCIe controller driver:

   - Add SDX65 endpoint compatible string to DT binding

   - Disable register write access after init for IP v2.3.3, v2.9.0

   - Use DWC helpers for enabling/disabling writes to DBI registers

   - Hide slot hotplug capability for IP v1.0.0, v1.9.0, v2.1.0, v2.3.2,
     v2.3.3, v2.7.0, v2.9.0

   - Reuse v2.3.2 post-init sequence for v2.4.0

  Renesas R-Car PCIe controller driver:

   - Remove unused static pcie_base and pcie_dev

  Rockchip PCIe controller driver:

   - Remove writes to unused registers

   - Write endpoint Device ID using correct register

   - Assert PCI Configuration Enable bit after probe so endpoint
     responds instead of generating Request Retry Status messages

   - Poll waiting for PHY PLLs to lock

   - Update RK3399 example DT binding to be valid

   - Use RK3399 PCIE_CLIENT_LEGACY_INT_CTRL to generate INTx instead of
     manually generating PCIe message

   - Use multiple windows to avoid address translation conflicts

   - Use u32 (not u16) when accessing 32-bit registers

   - Hide MSI-X Capability, since RK3399 can't generate MSI-X

   - Set endpoint controller required alignment to 256

  Synopsys DesignWare PCIe controller driver:

   - Wait for link to come up only if we've initiated link training

  Miscellaneous:

   - Add pci_clear_master() stub for non-CONFIG_PCI"

* tag 'pci-v6.5-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (116 commits)
  Documentation: PCI: correct spelling
  PCI: vmd: Fix uninitialized variable usage in vmd_enable_domain()
  PCI: xgene-msi: Convert to platform remove callback returning void
  PCI: tegra: Convert to platform remove callback returning void
  PCI: rockchip-host: Convert to platform remove callback returning void
  PCI: mvebu: Convert to platform remove callback returning void
  PCI: mt7621: Convert to platform remove callback returning void
  PCI: mediatek-gen3: Convert to platform remove callback returning void
  PCI: mediatek: Convert to platform remove callback returning void
  PCI: iproc: Convert to platform remove callback returning void
  PCI: hisi-error: Convert to platform remove callback returning void
  PCI: dwc: Convert to platform remove callback returning void
  PCI: j721e: Convert to platform remove callback returning void
  PCI: brcmstb: Convert to platform remove callback returning void
  PCI: altera-msi: Convert to platform remove callback returning void
  PCI: altera: Convert to platform remove callback returning void
  PCI: aardvark: Convert to platform remove callback returning void
  PCI: rcar: Use correct product family name for Renesas R-Car
  PCI: layerscape: Add the endpoint linkup notifier support
  PCI: endpoint: pci-epf-vntb: Fix typo in comments
  ...

Merge tag 'powerpc-6.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2023-06-30T16:20:08+00:00

Pull powerpc updates from Michael Ellerman:

 - Extend KCSAN support to 32-bit and BookE. Add some KCSAN annotations

 - Make ELFv2 ABI the default for 64-bit big-endian kernel builds, and
   use the -mprofile-kernel option (kernel specific ftrace ABI) for big
   endian ELFv2 kernels

 - Add initial Dynamic Execution Control Register (DEXCR) support, and
   allow the ROP protection instructions to be used on Power 10

 - Various other small features and fixes

Thanks to Aditya Gupta, Aneesh Kumar K.V, Benjamin Gray, Brian King,
Christophe Leroy, Colin Ian King, Dmitry Torokhov, Gaurav Batra, Jean
Delvare, Joel Stanley, Marco Elver, Masahiro Yamada, Nageswara R Sastry,
Nathan Chancellor, Naveen N Rao, Nayna Jain, Nicholas Piggin, Paul
Gortmaker, Randy Dunlap, Rob Herring, Rohan McLure, Russell Currey,
Sachin Sant, Timothy Pearson, Tom Rix, and Uwe Kleine-König.

* tag 'powerpc-6.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (76 commits)
  powerpc: remove checks for binutils older than 2.25
  powerpc: Fail build if using recordmcount with binutils v2.37
  powerpc/iommu: TCEs are incorrectly manipulated with DLPAR add/remove of memory
  powerpc/iommu: Only build sPAPR access functions on pSeries
  powerpc: powernv: Annotate data races in opal events
  powerpc: Mark writes registering ipi to host cpu through kvm and polling
  powerpc: Annotate accesses to ipi message flags
  powerpc: powernv: Fix KCSAN datarace warnings on idle_state contention
  powerpc: Mark [h]ssr_valid accesses in check_return_regs_valid
  powerpc: qspinlock: Enforce qnode writes prior to publishing to queue
  powerpc: qspinlock: Mark accesses to qnode lock checks
  powerpc/powernv/pci: Remove last IODA1 defines
  powerpc/powernv/pci: Remove MVE code
  powerpc/powernv/pci: Remove ioda1 support
  powerpc: 52xx: Make immr_id DT match tables static
  powerpc: mpc512x: Remove open coded "ranges" parsing
  powerpc: fsl_soc: Use of_range_to_resource() for "ranges" parsing
  powerpc: fsl: Use of_property_read_reg() to parse "reg"
  powerpc: fsl_rio: Use of_range_to_resource() for "ranges" parsing
  macintosh: Use of_property_read_reg() to parse "reg"
  ...