mirror of
https://github.com/cirosantilli/linux-kernel-module-cheat.git
synced 2026-01-25 11:11:35 +01:00
asm: make all text section labels .L local
To help with backtraces if we ever fix them due to the lkmc_asm_main_after_prologue debacle.
This commit is contained in:
@@ -16,6 +16,5 @@ LKMC_PROLOGUE
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*/
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adr x0, data_label
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ldr x1, =data_label
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label:
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LKMC_ASSERT_EQ_REG(x0, x1)
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LKMC_EPILOGUE
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@@ -3,9 +3,9 @@
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#include <lkmc.h>
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LKMC_PROLOGUE
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adrp x0, label
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adr x1, label
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label:
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adrp x0, .Llabel
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adr x1, .Llabel
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.Llabel:
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/* Clear the lower 12 bits. */
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bic x1, x1, 0xFF
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bic x1, x1, 0xF00
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@@ -6,14 +6,13 @@ LKMC_PROLOGUE
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/* Branch. */
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mov x0, 0x0
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cbz x0, ok
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cbz x0, .Lok
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LKMC_ASSERT_FAIL
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ok:
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.Lok:
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/* Don't branch. */
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mov x0, 0x1
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cbz x0, ko
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cbz x0, .Lko
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LKMC_EPILOGUE
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ko:
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.Lko:
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LKMC_ASSERT_FAIL
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@@ -17,10 +17,10 @@ LKMC_PROLOGUE
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* This could be used if the label is too far away for
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* adr relative addressing.
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*/
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movz x0, :abs_g2:label /* bits 32-47, overflow check */
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movk x0, :abs_g1_nc:label /* bits 16-31, no overflow check */
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movk x0, :abs_g0_nc:label /* bits 0-15, no overflow check */
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adr x1, label
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label:
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movz x0, :abs_g2:.Llabel /* bits 32-47, overflow check */
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movk x0, :abs_g1_nc:.Llabel /* bits 16-31, no overflow check */
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movk x0, :abs_g0_nc:.Llabel /* bits 0-15, no overflow check */
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adr x1, .Llabel
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.Llabel:
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LKMC_ASSERT_EQ_REG(x0, x1)
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LKMC_EPILOGUE
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@@ -27,11 +27,11 @@ LKMC_PROLOGUE
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* "LDR (literal)" instead of "LDR (immediate)":
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* https://stackoverflow.com/questions/28638981/howto-write-pc-relative-adressing-on-arm-asm/54480999#54480999
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*/
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ldr x0, pc_relative_ldr
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b 1f
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pc_relative_ldr:
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ldr x0, .Lpc_relative_ldr
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b 2f
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.Lpc_relative_ldr:
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.quad 0x123456789ABCDEF0
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1:
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2:
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LKMC_ASSERT_EQ(x0, =0x123456789ABCDEF0)
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/* Just for fun, we can also use relative numbers instead of labels.
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@@ -68,7 +68,7 @@ pc_relative_ldr:
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ldr x0, pc_relative_str
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LKMC_ASSERT_EQ(x0, =0x0)
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adr x1, pc_relative_str
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ldr x0, pc_relative_ldr
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ldr x0, .Lpc_relative_ldr
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str x0, [x1]
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ldr x0, pc_relative_str
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LKMC_ASSERT_EQ(x0, =0x123456789ABCDEF0)
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@@ -6,14 +6,14 @@
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data_label:
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.word 0x1234678
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LKMC_PROLOGUE
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adr r4, label
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adr r4, .Llabel
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/* objdump tells us that this uses the literal pool,
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* it does not get converted to adr, which is the better
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* alternative here.
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*/
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ldr r5, =label
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adrl r6, label
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label:
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ldr r5, =.Llabel
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adrl r6, .Llabel
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.Llabel:
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LKMC_ASSERT_EQ_REG(r4, r5)
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LKMC_ASSERT_EQ_REG(r4, r6)
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@@ -3,7 +3,7 @@
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#include <lkmc.h>
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LKMC_PROLOGUE
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/* Jump over the fail. 26-bit PC-relative. */
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b ok
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b .Lok
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LKMC_ASSERT_FAIL
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ok:
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.Lok:
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LKMC_EPILOGUE
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@@ -48,7 +48,6 @@ LKMC_PROLOGUE
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10:
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/* Another example with mov reading from pc. */
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pc_addr:
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mov r0, pc
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/* Why sub 8:
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* https://stackoverflow.com/questions/24091566/why-does-the-arm-pc-register-point-to-the-instruction-after-the-next-one-to-be-e
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@@ -46,8 +46,8 @@ LKMC_PROLOGUE
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* This construct is not possible in ARMv8 for str:
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* https://github.com/cirosantilli/linux-kernel-module-cheat#armv8-aarch64-str-instruction
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*/
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str r1, var_in_same_section
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var_in_same_section:
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str r1, .Lvar_in_same_section
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.Lvar_in_same_section:
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#endif
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/* = sign just doesn't make sense for str, you can't set the
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@@ -6,7 +6,7 @@
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#include <lkmc.h>
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LKMC_PROLOGUE
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jmp after_fail
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jmp .Lafter_fail
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LKMC_ASSERT_FAIL
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after_fail:
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.Lafter_fail:
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LKMC_EPILOGUE
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@@ -8,15 +8,15 @@
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LKMC_PROLOGUE
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/* Address in memory. */
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.section .rodata
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label_address: .quad memory_label
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label_address: .quad .Lmemory_label
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.text
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jmp *label_address
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LKMC_ASSERT_FAIL
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memory_label:
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.Lmemory_label:
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/* Address in register. */
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lea register_label(%rip), %rax
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lea .Lregister_label(%rip), %rax
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jmp *%rax
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LKMC_ASSERT_FAIL
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register_label:
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.Lregister_label:
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LKMC_EPILOGUE
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@@ -13,9 +13,9 @@ LKMC_PROLOGUE
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*/
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mov $0, %rax
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mov $3, %rcx
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loop_label:
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.Lloop_label:
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inc %rax
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loop loop_label
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loop .Lloop_label
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LKMC_ASSERT_EQ(%rax, $3)
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/* LOOPE
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@@ -37,10 +37,10 @@ loop_label:
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/* Array length. */
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mov $4, %rcx
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mov $-1, %rax
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loope_label:
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.Lloope_label:
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inc %rax
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cmpb $0, loope_array(%rax)
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loope loope_label
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loope .Lloope_label
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/* The first non-zero item (1) was at index 2. */
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LKMC_ASSERT_EQ(%rax, $2)
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