STRUCT ACRN_REGS(9)

💖 struct acrn_regs(9) 💖

okay so bestie, welcome to the glow-up doc for struct acrn_regs — the registers structure of a User VM ✨ (this is the Kernel API Manual babe, we're in the big leagues now 👑)

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✨ NAME ✨

struct acrn_regs — the registers structure of a User VM 🖥️💅

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🎀 SYNOPSIS 🎀

struct acrn_regs {
    struct acrn_gp_regs             gprs;
    struct acrn_descriptor_ptr      gdt;
    struct acrn_descriptor_ptr      idt;
    __le64 rip;
    __le64 cs_base;
    __le64 cr0;
    __le64 cr4;
    __le64 cr3;
    __le64 ia32_efer;
    __le64 rflags;
    __le64 reserved_64[4];
    __le32 cs_ar;
    __le32 cs_limit;
    __le32 reserved_32[3];
    __le16 cs_sel;
    __le16 ss_sel;
    __le16 ds_sel;
    __le16 es_sel;
    __le16 fs_sel;
    __le16 gs_sel;
    __le16 ldt_sel;
    __le16 tr_sel;
 };

ngl that's a lot of fields and every single one of them is iconic in its own way 🫶 let's go through them one by one, no skipping, we don't do that here 🍓

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🌸 Members 🌸

• gprs — the general registers, your everyday faves 💫
• gdt — the Global Descriptor Table, main character energy fr fr
• idt — the Interrupt Descriptor Table, she interrupts (respectfully) 😭
• rip — value of register RIP, the "where are we even going" register
• cs_base — base of the code segment selector 🧭
• cr0 — value of register CR0
• cr4 — value of register CR4
• cr3 — value of register CR3, the control-register girlies are all here 💅
• ia32_efer — value of the IA32_EFER MSR ✨
• rflags — value of register RFLAGS (yes that one, she's got flags 🚩)
• reserved_64 — reserved and must be 0 ⚠️ like, do not touch, this is not your moment
• cs_ar — attribute field of the code segment selector
• cs_limit — limit field of the code segment selector
• reserved_32 — reserved and must be 0 ⚠️ same deal bestie, hands off
• cs_sel — value of the code segment selector
• ss_sel — value of the stack segment selector 📚
• ds_sel — value of the data segment selector
• es_sel — value of the extra segment selector
• fs_sel — value of the FS selector
• gs_sel — value of the GS selector
• ldt_sel — value of the LDT descriptor selector
• tr_sel — value of the TSS descriptor selector 🧚

lowkey important: reserved_64 and reserved_32 are reserved and must be 0 — that's not a vibe suggestion, that's the rule 😤✨

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🦋 SEE ALSO 🦋

the kernel file is ./include/uapi/linux/acrn.h and honestly the whole friend group is here, go say hi 💖

• struct acrn_mmio_request(9)
• struct acrn_pio_request(9)
• struct acrn_pci_request(9)
• struct acrn_io_request(9)
• struct acrn_ioreq_notify(9)
• struct acrn_vm_creation(9)
• struct acrn_gp_regs(9)
• struct acrn_descriptor_ptr(9)
• struct acrn_vcpu_regs(9)
• struct acrn_vm_memmap(9)
• struct acrn_ptdev_irq(9)
• struct acrn_pcidev(9)
• struct acrn_mmio_dev_res(9)
• struct acrn_mmiodev(9)
• struct acrn_vdev(9)
• struct acrn_msi_entry(9)
• struct acrn_cstate_data(9)
• struct acrn_pstate_data(9)
• struct acrn_ioeventfd(9)
• struct acrn_irqfd(9)

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and that's the whole page bestie, you ate that 💅✨

this cutie lives in ./include/uapi/linux and the version/date stamp on her is October 2026 — so yeah, she's from the future, we stan a forward-thinking icon 🕰️👑 mwah, go read the kernel source 🫶💜