x86/asm: Always set A (accessed) flag in GDT descriptors

We have no known use for having the CPU track whether GDT descriptors
have been accessed or not.

Simplify the code by adding the flag to the common flags and removing
it everywhere else.

Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20231219151200.2878271-5-vegard.nossum@oracle.com

x86/asm: Replace magic numbers in GDT descriptors, script-generated change

Actually replace the numeric values by the new symbolic values.

I used this to find all the existing users of the GDT_ENTRY*() macros:

$ git grep -P 'GDT_ENTRY(_INIT)?\('

Some of the lines will exceed 80 characters, but some of them will be
shorter again in the next couple of patches.

Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20231219151200.2878271-4-vegard.nossum@oracle.com

x86/asm: Replace magic numbers in GDT descriptors, preparations

We'd like to replace all the magic numbers in various GDT descriptors
with new, semantically meaningful, symbolic values.

In order to be able to verify that the change doesn't cause any actual
changes to the compiled binary code, I've split the change into two
patches:

- Part 1 (this commit): everything _but_ actually replacing the numbers
- Part 2 (the following commit): _only_ replacing the numbers

The reason we need this split for verification is that including new
headers causes some spurious changes to the object files, mostly line
number changes in the debug info but occasionally other subtle codegen
changes.

Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20231219151200.2878271-3-vegard.nossum@oracle.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497

Based on 1 normalized pattern(s):

this file is part of the linux kernel and is made available under
the terms of the gnu general public license version 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 28 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.534229504@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86: remove zImage support

Impact: obsolete feature removal

The zImage kernel format has been functionally unused for a very long
time. It is just barely possible to build a modern kernel that still
fits within the zImage size limit, but it is highly unlikely that
anyone ever uses it. Furthermore, although it is still supported by
most bootloaders, it has been at best poorly tested (or not tested at
all); some bootloaders are even known to not support zImage at all and
not having even noticed.

Also remove some really obsolete constants that no longer have any
meaning.

LKML-Reference: <49B703D4.1000008@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x86: unify and correct the GDT_ENTRY() macro

Impact: None (cleanup only)

Merge the GDT_ENTRY() macro between arch/x86/boot/pm.c and
arch/x86/kernel/acpi/sleep.c and put the new one in
<asm-x86/segment.h>.

While we're at it, correct the bitmasks for the limit and flags. The
new version relies on using ULL constants in order to cause type
promotion rather than explicit casts; this avoids having to include
<linux/types.h> in <asm-x86/segments.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x86: unify and correct the GDT_ENTRY() macro

Merge the GDT_ENTRY() macro between arch/x86/boot/pm.c and
arch/x86/kernel/acpi/sleep.c and put the new one in
<asm-x86/segment.h>.

While we're at it, correct the bitmasks for the limit and flags. The
new version relies on using ULL constants in order to cause type
promotion rather than explicit casts; this avoids having to include
<linux/types.h> in <asm-x86/segments.h>.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x86: remove pointless comments

Remove old comments that include the old arch/i386 directory.

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86: coding style fix to arch/x86/boot/pm.c

Before:
total: 1 errors, 0 warnings, 178 lines checked
After:
total: 0 errors, 0 warnings, 178 lines checked

No code changed:

arch/x86/boot/pm.o:

text data bss dec hex filename
351 0 6 357 165 pm.o.before
351 0 6 357 165 pm.o.after

md5:
81de3616bceb29691bf835bb62a84ff1 pm.o.before.asm
81de3616bceb29691bf835bb62a84ff1 pm.o.after.asm

Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86 setup: correct the base in the GDT_ENTRY() macro

The GDT_ENTRY() macro in pm.c would incorrectly cut the bottom 8 bits
off the base. We didn't define any bases with the bottom 8 bits
nonzero, so it is a non-manifest bug, but it's still a bug.

Pointed out by John Smith <johnsmith9344@gmail.com>.
Cc: John Smith <johnsmith9344@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86 setup: initialize LDTR and TR to make life easier to Intel VT

Intel VT doesn't like to engage when the protected-mode state isn't
fully initialized. Make life easier for it by initializing LDTR (to
null) and TR (to a dummy hunk of low memory which will never actually
be touched.)

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

i386: move boot

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>