linux-stable.git/arch/mips/kernel/setup.c, branch v6.7.2

mips: Fix incorrect max_low_pfn adjustment

2024-01-25T23:45:19+00:00

[ Upstream commit 0f5cc249ff73552d3bd864e62f85841dafaa107d ]

max_low_pfn variable is incorrectly adjusted if the kernel is built with
high memory support and the later is detected in a running system, so the
memory which actually can be directly mapped is getting into the highmem
zone. See the ZONE_NORMAL range on my MIPS32r5 system:

> Zone ranges:
>   DMA      [mem 0x0000000000000000-0x0000000000ffffff]
>   Normal   [mem 0x0000000001000000-0x0000000007ffffff]
>   HighMem  [mem 0x0000000008000000-0x000000020fffffff]

while the zones are supposed to look as follows:

> Zone ranges:
>   DMA      [mem 0x0000000000000000-0x0000000000ffffff]
>   Normal   [mem 0x0000000001000000-0x000000001fffffff]
>   HighMem  [mem 0x0000000020000000-0x000000020fffffff]

Even though the physical memory within the range [0x08000000;0x20000000]
belongs to MMIO on our system, we don't really want it to be considered as
high memory since on MIPS32 that range still can be directly mapped.

Note there might be other problems caused by the max_low_pfn variable
misconfiguration. For instance high_memory variable is initialize with
virtual address corresponding to the max_low_pfn PFN, and by design it
must define the upper bound on direct map memory, then end of the normal
zone. That in its turn potentially may cause problems in accessing the
memory by means of the /dev/mem and /dev/kmem devices.

Let's fix the discovered misconfiguration then. It turns out the commit
a94e4f24ec83 ("MIPS: init: Drop boot_mem_map") didn't introduce the
max_low_pfn adjustment quite correct. If the kernel is built with high
memory support and the system is equipped with high memory, the
max_low_pfn variable will need to be initialized with PFN of the most
upper directly reachable memory address so the zone normal would be
correctly setup. On MIPS that PFN corresponds to PFN_DOWN(HIGHMEM_START).
If the system is built with no high memory support and one is detected in
the running system, we'll just need to adjust the max_pfn variable to
discard the found high memory from the system and leave the max_low_pfn as
is, since the later will be less than PFN_DOWN(HIGHMEM_START) anyway by
design of the for_each_memblock() loop performed a bit early in the
bootmem_init() method.

Fixes: a94e4f24ec83 ("MIPS: init: Drop boot_mem_map")
Signed-off-by: Serge Semin 
Signed-off-by: Thomas Bogendoerfer 
Signed-off-by: Sasha Levin

Merge tag 'tty-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2023-11-04T01:44:25+00:00

Pull tty and serial updates from Greg KH:
 "Here is the big set of tty/serial driver changes for 6.7-rc1. Included
  in here are:

   - console/vgacon cleanups and removals from Arnd

   - tty core and n_tty cleanups from Jiri

   - lots of 8250 driver updates and cleanups

   - sc16is7xx serial driver updates

   - dt binding updates

   - first set of port lock wrapers from Thomas for the printk fixes
     coming in future releases

   - other small serial and tty core cleanups and updates

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

* tag 'tty-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (193 commits)
  serdev: Replace custom code with device_match_acpi_handle()
  serdev: Simplify devm_serdev_device_open() function
  serdev: Make use of device_set_node()
  tty: n_gsm: add copyright Siemens Mobility GmbH
  tty: n_gsm: fix race condition in status line change on dead connections
  serial: core: Fix runtime PM handling for pending tx
  vgacon: fix mips/sibyte build regression
  dt-bindings: serial: drop unsupported samsung bindings
  tty: serial: samsung: drop earlycon support for unsupported platforms
  tty: 8250: Add note for PX-835
  tty: 8250: Fix IS-200 PCI ID comment
  tty: 8250: Add Brainboxes Oxford Semiconductor-based quirks
  tty: 8250: Add support for Intashield IX cards
  tty: 8250: Add support for additional Brainboxes PX cards
  tty: 8250: Fix up PX-803/PX-857
  tty: 8250: Fix port count of PX-257
  tty: 8250: Add support for Intashield IS-100
  tty: 8250: Add support for Brainboxes UP cards
  tty: 8250: Add support for additional Brainboxes UC cards
  tty: 8250: Remove UC-257 and UC-431
  ...

vgacon: clean up global screen_info instances

2023-10-17T08:17:02+00:00

To prepare for completely separating the VGA console screen_info from
the one used in EFI/sysfb, rename the vgacon instances and make them
local as much as possible.

ia64 and arm both have confurations with vgacon and efi, but the contents
never overlaps because ia64 has no EFI framebuffer, and arm only has
vga console on legacy platforms without EFI. Renaming these is required
before the EFI screen_info can be moved into drivers/firmware.

The ia64 vga console is actually registered in two places from
setup_arch(), but one of them is wrong, so drop the one in pcdp.c and
fix the one in setup.c to use the correct conditional.

x86 has to keep them together, as the boot protocol is used to switch
between VGA text console and framebuffer through the screen_info data.

Acked-by: Javier Martinez Canillas 
Acked-by: Khalid Aziz 
Acked-by: Helge Deller 
Signed-off-by: Arnd Bergmann 
Link: https://lore.kernel.org/r/20231009211845.3136536-7-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman

vgacon: remove screen_info dependency

2023-10-17T08:17:02+00:00

The vga console driver is fairly self-contained, and only used by
architectures that explicitly initialize the screen_info settings.

Chance every instance that picks the vga console by setting conswitchp
to call a function instead, and pass a reference to the screen_info
there.

Reviewed-by: Javier Martinez Canillas 
Acked-by: Khalid Azzi 
Acked-by: Helge Deller 
Signed-off-by: Arnd Bergmann 
Link: https://lore.kernel.org/r/20231009211845.3136536-6-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman

vgacon: rework screen_info #ifdef checks

2023-10-17T08:17:02+00:00

On non-x86 architectures, the screen_info variable is generally only
used for the VGA console where supported, and in some cases the EFI
framebuffer or vga16fb.

Now that we have a definite list of which architectures actually use it
for what, use consistent #ifdef checks so the global variable is only
defined when it is actually used on those architectures.

Loongarch and riscv have no support for vgacon or vga16fb, but
they support EFI firmware, so only that needs to be checked, and the
initialization can be removed because that is handled by EFI.
IA64 has both vgacon and EFI, though EFI apparently never uses
a framebuffer here.

Reviewed-by: Javier Martinez Canillas 
Reviewed-by: Thomas Zimmermann 
Reviewed-by: Khalid Aziz 
Acked-by: Helge Deller 
Signed-off-by: Arnd Bergmann 
Link: https://lore.kernel.org/r/20231009211845.3136536-3-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman

crash_core: change the prototype of function parse_crashkernel()

2023-10-04T17:41:58+00:00

Add two parameters 'low_size' and 'high' to function parse_crashkernel(),
later crashkernel=,high|low parsing will be added.  Make adjustments in
all call sites of parse_crashkernel() in arch.

Link: https://lkml.kernel.org/r/20230914033142.676708-3-bhe@redhat.com
Signed-off-by: Baoquan He 
Reviewed-by: Zhen Lei 
Cc: Catalin Marinas 
Cc: Chen Jiahao 
Signed-off-by: Andrew Morton

Merge tag 'x86-boot-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-06-26T20:39:10+00:00

Pull x86 boot updates from Thomas Gleixner:
 "Initialize FPU late.

  Right now FPU is initialized very early during boot. There is no real
  requirement to do so. The only requirement is to have it done before
  alternatives are patched.

  That's done in check_bugs() which does way more than what the function
  name suggests.

  So first rename check_bugs() to arch_cpu_finalize_init() which makes
  it clear what this is about.

  Move the invocation of arch_cpu_finalize_init() earlier in
  start_kernel() as it has to be done before fork_init() which needs to
  know the FPU register buffer size.

  With those prerequisites the FPU initialization can be moved into
  arch_cpu_finalize_init(), which removes it from the early and fragile
  part of the x86 bringup"

* tag 'x86-boot-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mem_encrypt: Unbreak the AMD_MEM_ENCRYPT=n build
  x86/fpu: Move FPU initialization into arch_cpu_finalize_init()
  x86/fpu: Mark init functions __init
  x86/fpu: Remove cpuinfo argument from init functions
  x86/init: Initialize signal frame size late
  init, x86: Move mem_encrypt_init() into arch_cpu_finalize_init()
  init: Invoke arch_cpu_finalize_init() earlier
  init: Remove check_bugs() leftovers
  um/cpu: Switch to arch_cpu_finalize_init()
  sparc/cpu: Switch to arch_cpu_finalize_init()
  sh/cpu: Switch to arch_cpu_finalize_init()
  mips/cpu: Switch to arch_cpu_finalize_init()
  m68k/cpu: Switch to arch_cpu_finalize_init()
  loongarch/cpu: Switch to arch_cpu_finalize_init()
  ia64/cpu: Switch to arch_cpu_finalize_init()
  ARM: cpu: Switch to arch_cpu_finalize_init()
  x86/cpu: Switch to arch_cpu_finalize_init()
  init: Provide arch_cpu_finalize_init()

mips/cpu: Switch to arch_cpu_finalize_init()

2023-06-16T08:16:00+00:00

check_bugs() is about to be phased out. Switch over to the new
arch_cpu_finalize_init() implementation.

No functional change.

Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/r/20230613224545.312438573@linutronix.de

mips: Move initrd_start check after initrd address sanitisation.

2023-05-23T09:01:38+00:00

PAGE_OFFSET is technically a virtual address so when checking the value of
initrd_start against it we should make sure that it has been sanitised from
the values passed by the bootloader. Without this change, even with a bootloader
that passes correct addresses for an initrd, we are failing to load it on MT7621
boards, for example.

Signed-off-by: Liviu Dudau 
Signed-off-by: Thomas Bogendoerfer

MIPS: Sink body of check_bugs_early() into its only call site

2023-04-22T21:29:00+00:00

If check_bugs_early() is not inlined, which a compiler is free to do
after commit ac7c3e4ff401 ("compiler: enable CONFIG_OPTIMIZE_INLINING
forcibly"), modpost would warn that check_bugs_early(), a non-init
function, refers to check_bugs64_early(), which is marked __init. This
would not result in any run time issues, as check_bugs_early() is only
called from setup_arch(), which is marked __init.

To avoid this potential warning, just sink the body of
check_bugs_early() into its single call site in setup_arch().

Signed-off-by: Nathan Chancellor 
Signed-off-by: Thomas Bogendoerfer