linux.git/arch/parisc/kernel/head.S, branch v5.10.258

parisc: Fix initial page table creation for boot

2026-04-18T08:30:56+00:00

commit 8475d8fe21ec9c7eb2faca555fbc5b68cf0d2597 upstream.

The KERNEL_INITIAL_ORDER value defines the initial size (usually 32 or
64 MB) of the page table during bootup. Up until now the whole area was
initialized with PTE entries, but there was no check if we filled too
many entries.  Change the code to fill up with so many entries that the
"_end" symbol can be reached by the kernel, but not more entries than
actually fit into the initial PTE tables.

Signed-off-by: Helge Deller 
Cc:  # v6.0+
Signed-off-by: Greg Kroah-Hartman

parisc: Prevent booting 64-bit kernels on PA1.x machines

2023-11-28T16:54:59+00:00

commit a406b8b424fa01f244c1aab02ba186258448c36b upstream.

Bail out early with error message when trying to boot a 64-bit kernel on
32-bit machines. This fixes the previous commit to include the check for
true 64-bit kernels as well.

Signed-off-by: Helge Deller 
Fixes: 591d2108f3abc ("parisc: Add runtime check to prevent PA2.0 kernels on PA1.x machines")
Cc:   # v6.0+
Signed-off-by: Greg Kroah-Hartman

parisc: Add runtime check to prevent PA2.0 kernels on PA1.x machines

2022-09-15T09:32:03+00:00

[ Upstream commit 591d2108f3abc4db9f9073cae37cf3591fd250d6 ]

If a 32-bit kernel was compiled for PA2.0 CPUs, it won't be able to run
on machines with PA1.x CPUs. Add a check and bail out early if a PA1.x
machine is detected.

Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin

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

2020-06-09T16:39:13+00:00

The replacement of  with  made the include
of the latter in the middle of asm includes.  Fix this up with the aid of
the below script and manual adjustments here and there.

	import sys
	import re

	if len(sys.argv) is not 3:
	    print "USAGE: %s  " % (sys.argv[0])
	    sys.exit(1)

	hdr_to_move="#include " % sys.argv[2]
	moved = False
	in_hdrs = False

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

mm: introduce include/linux/pgtable.h

2020-06-09T16:39:13+00:00

The include/linux/pgtable.h is going to be the home of generic page table
manipulation functions.

Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and
make the latter include asm/pgtable.h.

Signed-off-by: Mike Rapoport 
Signed-off-by: Andrew Morton 
Cc: Arnd Bergmann 
Cc: Borislav Petkov 
Cc: Brian Cain 
Cc: Catalin Marinas 
Cc: Chris Zankel 
Cc: "David S. Miller" 
Cc: Geert Uytterhoeven 
Cc: Greentime Hu 
Cc: Greg Ungerer 
Cc: Guan Xuetao 
Cc: Guo Ren 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: Ingo Molnar 
Cc: Ley Foon Tan 
Cc: Mark Salter 
Cc: Matthew Wilcox 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Nick Hu 
Cc: Paul Walmsley 
Cc: Richard Weinberger 
Cc: Rich Felker 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Vincent Chen 
Cc: Vineet Gupta 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds

parisc: Use __ro_after_init in head.S

2019-05-10T19:00:44+00:00

Signed-off-by: Helge Deller

parisc: Rename LEVEL to PA_ASM_LEVEL to avoid name clash with DRBD code

2019-05-05T22:09:56+00:00

LEVEL is a very common word, and now after many years it suddenly
clashed with another LEVEL define in the DRBD code.
Rename it to PA_ASM_LEVEL instead.

Reported-by: kbuild test robot 
Signed-off-by: Helge Deller 
Cc:

parisc: enable wide mode early

2019-05-03T21:47:40+00:00

The idle task might have been allocated above 4GB. With the current code
we cannot access that memory because the CPU is still running in narrow
mode.
This was found on a J5000 machine and the patch is required to enable
SPARSEMEM on that machine.

Signed-off-by: Sven Schnelle 
Signed-off-by: Helge Deller

parisc: Check if secondary CPUs want own PDC calls

2018-03-02T09:04:46+00:00

The architecture specification says (for 64-bit systems): PDC is a per
processor resource, and operating system software must be prepared to
manage separate pointers to PDCE_PROC for each processor.  The address
of PDCE_PROC for the monarch processor is stored in the Page Zero
location MEM_PDC. The address of PDCE_PROC for each non-monarch
processor is passed in gr26 when PDCE_RESET invokes OS_RENDEZ.

Currently we still use one PDC for all CPUs, but in case we face a
machine which is following the specification let's warn about it.

Signed-off-by: Helge Deller

parisc: Fix ftrace function tracer

2016-04-14T15:47:19+00:00

Fix the FTRACE function tracer for 32- and 64-bit kernel.
The former code was horribly broken.

Reimplement most coding in assembly and utilize optimizations, e.g. put
mcount() and ftrace_stub() into one L1 cacheline.

Signed-off-by: Helge Deller