Add text patching api's to use in subsequent jump_label implementation. We use
a new fixmap FIX_TEXT_POKE0 entry to temporarily override MMU mappings to allow
read only text pages to be written to.
Previously, __set_fix was marked with __init as it was only used during the
EARLYCON stage. Now that TEXT_POKE mappings require post-init usage
(e.g., FIX_TEXT_POKE0), keeping __init would cause runtime bugs whenset_fixmap
accesses invalid memory. Thus, we remove the __init flag to ensure __set_fix
remains valid beyond initialization.
A new function patch_insn_write is exposed to allow single instruction patching.
Link: https://lore.kernel.org/openrisc/aJIC8o1WmVHol9RY@antec/T/#t
Signed-off-by: chenmiao <chenmiao.ku@gmail.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
With commit 53c98e35dc ("openrisc: mm: remove unneeded early ioremap
code") it was commented that early ioremap was not used in OpenRISC. I
acked this but was wrong, earlycon was using it. Earlycon setup now
fails with the below trace:
Kernel command line: earlycon
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at mm/ioremap.c:23
generic_ioremap_prot+0x118/0x130
Modules linked in:
CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted
6.11.0-rc5-00001-gce02fd891c38-dirty #141
Call trace:
[<(ptrval)>] dump_stack_lvl+0x7c/0x9c
[<(ptrval)>] dump_stack+0x1c/0x2c
[<(ptrval)>] __warn+0xb4/0x108
[<(ptrval)>] ? generic_ioremap_prot+0x118/0x130
[<(ptrval)>] warn_slowpath_fmt+0x60/0x98
[<(ptrval)>] generic_ioremap_prot+0x118/0x130
[<(ptrval)>] ioremap_prot+0x20/0x30
[<(ptrval)>] of_setup_earlycon+0xd4/0x2e0
[<(ptrval)>] early_init_dt_scan_chosen_stdout+0x18c/0x1c8
[<(ptrval)>] param_setup_earlycon+0x3c/0x60
[<(ptrval)>] do_early_param+0xb0/0x118
[<(ptrval)>] parse_args+0x184/0x4b8
[<(ptrval)>] ? start_kernel+0x0/0x78c
[<(ptrval)>] parse_early_options+0x40/0x50
[<(ptrval)>] ? do_early_param+0x0/0x118
[<(ptrval)>] parse_early_param+0x48/0x68
[<(ptrval)>] ? start_kernel+0x318/0x78c
[<(ptrval)>] ? start_kernel+0x0/0x78c
---[ end trace 0000000000000000 ]---
To fix this we could either implement early_ioremap again or implement
fixmap. In this patch we choose the later option of implementing basic
fixmap support.
While fixing this we also remove the old FIX_IOREMAP slots that were
used by early ioremap code. That code was also removed by commit
53c98e35dc ("openrisc: mm: remove unneeded early ioremap code") but
these definitions were not cleaned up.
Fixes: 53c98e35dc ("openrisc: mm: remove unneeded early ioremap code")
Signed-off-by: Stafford Horne <shorne@gmail.com>
Openrisc's implementation of fix_to_virt() & virt_to_fix() share same
functionality with ones of asm generic.
Plus, generic version of fix_to_virt() can trap invalid index at compile
time.
Thus, Replace the arch-specific implementations with asm generic's ones.
Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
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>
openrisc's asm/fixmap.h uses the BUG() and BUG_ON() macros but relies on
implict inclusion of linux/bug.h which means that changes in other
headers could break the build. Thus, add an explicit include.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Stafford Horne <shorne@gmail.com>
chenmiao
Stafford Horne
Dawei Li
Thomas Gleixner
Tobias Klauser
Jonas Bonn