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| author | Niklas Cassel <cassel@kernel.org> | 2026-09-16 15:00:32 +0200 |
|---|---|---|
| committer | Niklas Cassel <cassel@kernel.org> | 2026-09-16 16:18:00 +0200 |
| commit | 8d836581f9b1f57ceaa2b47654754ef1260b410b (patch) | |
| tree | 1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /arch/x86/boot/pm.c | |
| download | linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip | |
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with:
Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301:
ERROR: Unexpected indentation. [docutils]
The Return: section of ata_dsm_trim_pages() ends its first sentence with
a colon and continues with an indented bullet list. reStructuredText
requires a blank line before an indented block, so docutils chokes on
the list.
Simply adding the missing blank line does not work either: Return: is a
kernel-doc "special section", which is terminated by the first blank
line, so the bullet list would end up in the Description section,
detached from the sentence introducing it.
Spell the two bounds out as prose instead, so that the Return: section
stays self-contained. Documentation-only change.
Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND")
Reported-by: Thomas Huth <thuth@redhat.com>
Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'arch/x86/boot/pm.c')
| -rw-r--r-- | arch/x86/boot/pm.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/x86/boot/pm.c b/arch/x86/boot/pm.c new file mode 100644 index 000000000..5941f930f --- /dev/null +++ b/arch/x86/boot/pm.c @@ -0,0 +1,125 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* -*- linux-c -*- ------------------------------------------------------- * + * + * Copyright (C) 1991, 1992 Linus Torvalds + * Copyright 2007 rPath, Inc. - All Rights Reserved + * + * ----------------------------------------------------------------------- */ + +/* + * Prepare the machine for transition to protected mode. + */ + +#include "boot.h" +#include <asm/desc_defs.h> +#include <asm/segment.h> + +/* + * Invoke the realmode switch hook if present; otherwise + * disable all interrupts. + */ +static void realmode_switch_hook(void) +{ + if (boot_params.hdr.realmode_swtch) { + asm volatile("lcallw *%0" + : : "m" (boot_params.hdr.realmode_swtch) + : "eax", "ebx", "ecx", "edx"); + } else { + asm volatile("cli"); + outb(0x80, 0x70); /* Disable NMI */ + io_delay(); + } +} + +/* + * Disable all interrupts at the legacy PIC. + */ +static void mask_all_interrupts(void) +{ + outb(0xff, 0xa1); /* Mask all interrupts on the secondary PIC */ + io_delay(); + outb(0xfb, 0x21); /* Mask all but cascade on the primary PIC */ + io_delay(); +} + +/* + * Reset IGNNE# if asserted in the FPU. + */ +static void reset_coprocessor(void) +{ + outb(0, 0xf0); + io_delay(); + outb(0, 0xf1); + io_delay(); +} + +/* + * Set up the GDT + */ + +struct gdt_ptr { + u16 len; + u32 ptr; +} __attribute__((packed)); + +static void setup_gdt(void) +{ + /* There are machines which are known to not boot with the GDT + being 8-byte unaligned. Intel recommends 16 byte alignment. */ + static const u64 boot_gdt[] __attribute__((aligned(16))) = { + /* CS: code, read/execute, 4 GB, base 0 */ + [GDT_ENTRY_BOOT_CS] = GDT_ENTRY(DESC_CODE32, 0, 0xfffff), + /* DS: data, read/write, 4 GB, base 0 */ + [GDT_ENTRY_BOOT_DS] = GDT_ENTRY(DESC_DATA32, 0, 0xfffff), + /* TSS: 32-bit tss, 104 bytes, base 4096 */ + /* We only have a TSS here to keep Intel VT happy; + we don't actually use it for anything. */ + [GDT_ENTRY_BOOT_TSS] = GDT_ENTRY(DESC_TSS32, 4096, 103), + }; + /* Xen HVM incorrectly stores a pointer to the gdt_ptr, instead + of the gdt_ptr contents. Thus, make it static so it will + stay in memory, at least long enough that we switch to the + proper kernel GDT. */ + static struct gdt_ptr gdt; + + gdt.len = sizeof(boot_gdt)-1; + gdt.ptr = (u32)&boot_gdt + (ds() << 4); + + asm volatile("lgdtl %0" : : "m" (gdt)); +} + +/* + * Set up the IDT + */ +static void setup_idt(void) +{ + static const struct gdt_ptr null_idt = {0, 0}; + asm volatile("lidtl %0" : : "m" (null_idt)); +} + +/* + * Actual invocation sequence + */ +void go_to_protected_mode(void) +{ + /* Hook before leaving real mode, also disables interrupts */ + realmode_switch_hook(); + + /* Enable the A20 gate */ + if (enable_a20()) { + puts("A20 gate not responding, unable to boot...\n"); + die(); + } + + /* Reset coprocessor (IGNNE#) */ + reset_coprocessor(); + + /* Mask all interrupts in the PIC */ + mask_all_interrupts(); + + /* Actual transition to protected mode... */ + setup_idt(); + setup_gdt(); + protected_mode_jump(boot_params.hdr.code32_start, + (u32)&boot_params + (ds() << 4)); +} |
