diff options
Diffstat (limited to 'results/classifier/user-mode-bugs/2606')
| -rw-r--r-- | results/classifier/user-mode-bugs/2606 | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/results/classifier/user-mode-bugs/2606 b/results/classifier/user-mode-bugs/2606 new file mode 100644 index 000000000..5b1b0ec41 --- /dev/null +++ b/results/classifier/user-mode-bugs/2606 @@ -0,0 +1,200 @@ + + +PowerPC host code is broken on Darwin +Description of problem: +Existing code is just wrong for Darwin ppc, it won’t compile. Assembler syntax needs to be fixed and likely adjusted to correct ABI. +Steps to reproduce: +1. Run the build of qemu on Darwin ppc, see it fail. +Additional information: +This is a patch I used earlier to fix the build (together with few minor unrelated to powerpc fixes): +``` +--- common-user/host/ppc/safe-syscall.inc.S.orig 2022-04-20 03:10:27.000000000 +0800 ++++ common-user/host/ppc/safe-syscall.inc.S 2023-08-18 18:08:15.000000000 +0800 +@@ -25,17 +25,11 @@ + # else + # error "Unknown ABI" + # endif +-#endif +- +-#ifndef _CALL_SYSV +-# error "Unsupported ABI" + #endif + +- + .global safe_syscall_base + .global safe_syscall_start + .global safe_syscall_end +- .type safe_syscall_base, @function + + .text + +@@ -47,11 +41,8 @@ + * arguments being syscall arguments (also 'long'). + */ + safe_syscall_base: +- .cfi_startproc +- stwu 1, -8(1) +- .cfi_def_cfa_offset 8 +- stw 30, 4(1) +- .cfi_offset 30, -4 ++ stwu r1, -8(r1) ++ stw r30, 4(r1) + + /* + * We enter with r3 == &signal_pending +@@ -64,14 +55,14 @@ + * and returns the result in r3 + * Shuffle everything around appropriately. + */ +- mr 30, 3 /* signal_pending */ +- mr 0, 4 /* syscall number */ +- mr 3, 5 /* syscall arguments */ +- mr 4, 6 +- mr 5, 7 +- mr 6, 8 +- mr 7, 9 +- mr 8, 10 ++ mr r30, r3 /* signal_pending */ ++ mr r0, r4 /* syscall number */ ++ mr r3, r5 /* syscall arguments */ ++ mr r4, r6 ++ mr r5, r7 ++ mr r6, r8 ++ mr r7, r9 ++ mr r8, r10 + + /* + * This next sequence of code works in conjunction with the +@@ -83,25 +74,22 @@ + */ + safe_syscall_start: + /* if signal_pending is non-zero, don't do the call */ +- lwz 12, 0(30) +- cmpwi 0, 12, 0 ++ lwz r12, 0(r30) ++ cmpwi cr0, r12, 0 + bne- 2f + sc + safe_syscall_end: + /* code path when we did execute the syscall */ +- lwz 30, 4(1) /* restore r30 */ +- addi 1, 1, 8 /* restore stack */ +- .cfi_restore 30 +- .cfi_def_cfa_offset 0 ++ lwz r30, 4(r1) /* restore r30 */ ++ addi r1, r1, 8 /* restore stack */ ++ + bnslr+ /* return on success */ + b safe_syscall_set_errno_tail + + /* code path when we didn't execute the syscall */ +-2: lwz 30, 4(1) +- addi 1, 1, 8 +- addi 3, 0, QEMU_ERESTARTSYS ++2: lwz r30, 4(r1) ++ addi r1, r1, 8 ++ addi r3, 0, QEMU_ERESTARTSYS + b safe_syscall_set_errno_tail + +- .cfi_endproc +- + .size safe_syscall_base, .-safe_syscall_base + + +--- common-user/host/ppc64/safe-syscall.inc.S.orig 2022-04-20 03:10:27.000000000 +0800 ++++ common-user/host/ppc64/safe-syscall.inc.S 2022-05-31 13:23:21.000000000 +0800 +@@ -13,7 +13,6 @@ + .global safe_syscall_base + .global safe_syscall_start + .global safe_syscall_end +- .type safe_syscall_base, @function + + .text + +@@ -23,19 +22,10 @@ + * second one the system call number (as a 'long'), and all further + * arguments being syscall arguments (also 'long'). + */ +-#if _CALL_ELF == 2 +-safe_syscall_base: +- .cfi_startproc +- .localentry safe_syscall_base,0 +-#else +- .section ".opd","aw" ++ + .align 3 + safe_syscall_base: +- .quad .L.safe_syscall_base,.TOC.@tocbase,0 +- .previous +-.L.safe_syscall_base: +- .cfi_startproc +-#endif ++ + /* We enter with r3 == &signal_pending + * r4 == syscall number + * r5 ... r10 == syscall arguments +@@ -46,16 +36,15 @@ + * and returns the result in r3 + * Shuffle everything around appropriately. + */ +- std 14, 16(1) /* Preserve r14 in SP+16 */ +- .cfi_offset 14, 16 +- mr 14, 3 /* signal_pending */ +- mr 0, 4 /* syscall number */ +- mr 3, 5 /* syscall arguments */ +- mr 4, 6 +- mr 5, 7 +- mr 6, 8 +- mr 7, 9 +- mr 8, 10 ++ std r14, 16(r1) /* Preserve r14 in SP+16 */ ++ mr r14, r3 /* signal_pending */ ++ mr r0, r4 /* syscall number */ ++ mr r3, r5 /* syscall arguments */ ++ mr r4, r6 ++ mr r5, r7 ++ mr r6, r8 ++ mr r7, r9 ++ mr r8, r10 + + /* This next sequence of code works in conjunction with the + * rewind_if_safe_syscall_function(). If a signal is taken +@@ -66,29 +55,20 @@ + */ + safe_syscall_start: + /* if signal_pending is non-zero, don't do the call */ +- lwz 12, 0(14) +- cmpwi 0, 12, 0 ++ ld r12, 0(r14) ++ cmpdi cr0, r12, 0 + bne- 2f + sc + safe_syscall_end: + /* code path when we did execute the syscall */ +- ld 14, 16(1) /* restore r14 */ ++ ld r14, 16(r1) /* restore r14 */ + bso- 1f + blr + + /* code path when we didn't execute the syscall */ +-2: ld 14, 16(1) /* restore r14 */ +- addi 3, 0, QEMU_ERESTARTSYS ++2: ld r14, 16(r1) /* restore r14 */ ++ addi r3, 0, QEMU_ERESTARTSYS + + /* code path setting errno */ + 1: b safe_syscall_set_errno_tail + nop /* per abi, for the linker to modify */ +- +- .cfi_endproc +- +-#if _CALL_ELF == 2 +- .size safe_syscall_base, .-safe_syscall_base +-#else +- .size safe_syscall_base, .-.L.safe_syscall_base +- .size .L.safe_syscall_base, .-.L.safe_syscall_base +-#endif +``` +(Obviously, it is not made in a portable way – that was not needed at the time.) + +Unfortunately, while build itself worked, the binary crashed on launch. So something is not quite right, maybe with ABI compliance. |