arch/arm/mm/abort-macro.S

File Facts

System

Linux kernel

Corpus path

arch/arm/mm/abort-macro.S

Extension

.S

Size

1188 bytes

Lines

40

Domain

Architecture Layer

Bucket

arch/arm

Inferred role

Architecture Layer: arch/arm

Status

atlas-only

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

• CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

• No C-style include directives detected by the generator.

Detected Declarations

• No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

.macro	do_thumb_abort, fsr, pc, psr, tmp
	tst	\psr, #PSR_T_BIT
	beq	not_thumb
	ldrh	\tmp, [\pc]			@ Read aborted Thumb instruction
	uaccess_disable ip			@ disable userspace access
	and	\tmp, \tmp, # 0xfe00		@ Mask opcode field
	cmp	\tmp, # 0x5600			@ Is it ldrsb?
	orreq	\tmp, \tmp, #1 << 11		@ Set L-bit if yes
	tst	\tmp, #1 << 11			@ L = 0 -> write
	orreq	\fsr, \fsr, #1 << 11		@ yes.
	b	do_DataAbort
not_thumb:
	.endm

/*
 * We check for the following instruction encoding for LDRD.
 *
 * [27:25] == 000
 *   [7:4] == 1101
 *    [20] == 0
 */
	.macro	teq_ldrd, tmp, insn
	mov	\tmp, #0x0e100000
	orr	\tmp, #0x000000f0
	and	\tmp, \insn, \tmp
	teq	\tmp, #0x000000d0
	.endm

Annotation

• Atlas domain: Architecture Layer / arch/arm.
• Implementation status: atlas-only.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.