qemu/target/arm
Masahiro Yamada 21bf9b06cb target/arm/arm-semi: fix SYS_OPEN to return nonzero filehandle
According to the specification "Semihosting for AArch32 and Aarch64",
the SYS_OPEN operation should return:

 - A nonzero handle if the call is successful
 - -1 if the call is not successful

So, it should never return 0.

Prior to commit 35e9a0a8ce ("target/arm/arm-semi: Make semihosting
code hand out its own file descriptors"), the guest fd matched to the
host fd. It returned a nonzero handle on success since the fd 0 is
already used for stdin.

Now that the guest fd is the index of guestfd_array, it starts from 0.

I noticed this issue particularly because Trusted Firmware-A built with
PLAT=qemu is no longer working. Its io_semihosting driver only handles
a positive return value as a valid filehandle.

Basically, there are two ways to fix this:

  - Use (guestfd - 1) as the index of guestfs_arrary. We need to insert
    increment/decrement to convert the guestfd and the array index back
    and forth.

  - Keep using guestfd as the index of guestfs_array. The first entry
    of guestfs_array is left unused.

I thought the latter is simpler. We end up with wasting a small piece
of memory for the unused first entry of guestfd_array, but this is
probably not a big deal.

Fixes: 35e9a0a8ce ("target/arm/arm-semi: Make semihosting code hand out its own file descriptors")
Cc: qemu-stable@nongnu.org
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200109041228.10131-1-masahiroy@kernel.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-01-17 14:09:30 +00:00
..
a32-uncond.decode target/arm: Convert Unallocated memory hint 2019-09-05 13:23:03 +01:00
a32.decode target/arm: Convert SVC 2019-09-05 13:23:03 +01:00
arch_dump.c
arm_ldst.h target/arm: fetch code with translator_ld 2019-10-28 15:12:38 +00:00
arm-powerctl.c arm/arm-powerctl: rebuild hflags after setting CP15 bits in arm_set_cpu_on() 2019-12-20 14:03:00 +00:00
arm-powerctl.h target/arm/arm-powerctl: Add new arm_set_cpu_on_and_reset() 2019-02-28 11:03:04 +00:00
arm-semi.c target/arm/arm-semi: fix SYS_OPEN to return nonzero filehandle 2020-01-17 14:09:30 +00:00
cpu64.c target/arm: Add support for DC CVAP & DC CVADP ins 2019-12-16 10:46:35 +00:00
cpu-param.h tcg: Split out target/arch/cpu-param.h 2019-06-10 07:03:34 -07:00
cpu-qom.h hw/core: Move cpu.c, cpu.h from qom/ to hw/core/ 2019-08-21 13:24:01 +02:00
cpu.c target/arm: Prepare generic timer for per-platform CNTFRQ 2019-12-20 14:02:59 +00:00
cpu.h target/arm: Abstract the generic timer frequency 2019-12-20 14:02:59 +00:00
crypto_helper.c
debug_helper.c target/arm: Move debug routines to debug_helper.c 2019-07-04 17:14:43 +01:00
gdbstub64.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
gdbstub.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
helper-a64.c tcg: Search includes from the project root source directory 2020-01-15 15:13:10 -10:00
helper-a64.h target/arm: Split helper_msr_i_pstate into 3 2019-03-05 15:55:08 +00:00
helper-sve.h
helper.c target/arm: only update pc after semihosting completes 2020-01-09 11:41:29 +00:00
helper.h target/arm: ensure we use current exception state after SCR update 2019-12-16 10:52:58 +00:00
idau.h
internals.h target/arm: Split out arm_mmu_idx_el 2019-10-24 17:16:28 +01:00
iwmmxt_helper.c
kvm32.c target/arm/kvm: scratch vcpu: Preserve input kvm_vcpu_init features 2019-11-01 20:40:59 +00:00
kvm64.c target/arm/kvm: host cpu: Add support for sve<N> properties 2019-11-01 20:40:59 +00:00
kvm_arm.h target/arm/cpu64: max cpu: Support sve properties with KVM 2019-11-01 20:40:59 +00:00
kvm-consts.h
kvm-stub.c Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
kvm.c kvm: introduce kvm_kernel_irqchip_* functions 2019-12-17 19:32:45 +01:00
m_helper.c target/arm: only update pc after semihosting completes 2020-01-09 11:41:29 +00:00
machine.c target/arm: Rebuild hflags at EL changes 2019-10-24 17:16:28 +01:00
Makefile.objs target/arm: Add skeleton for T16 decodetree 2019-09-05 13:23:03 +01:00
monitor.c target/arm/cpu64: max cpu: Introduce sve<N> properties 2019-11-01 20:40:59 +00:00
neon_helper.c target/arm: Use tcg_gen_abs_i64 and tcg_gen_gvec_abs 2019-05-13 22:52:08 +00:00
op_addsub.h
op_helper.c target/arm: Handle AArch32 CP15 trapping via HSTR_EL2 2019-12-16 10:46:35 +00:00
pauth_helper.c target/arm: Fix output of PAuth Auth 2019-06-13 15:14:03 +01:00
psci.c sysemu: Split sysemu/runstate.h off sysemu/sysemu.h 2019-08-16 13:37:36 +02:00
sve_helper.c tcg: Search includes from the project root source directory 2020-01-15 15:13:10 -10:00
sve.decode
t16.decode target/arm: Convert T16, long branches 2019-09-05 13:23:04 +01:00
t32.decode target/arm: Convert TT 2019-09-05 13:23:03 +01:00
tlb_helper.c target/arm: Move TLB related routines to tlb_helper.c 2019-07-01 17:29:01 +01:00
trace-events trace-events: Shorten file names in comments 2019-03-22 16:18:07 +00:00
translate-a64.c tcg: Search includes from the project root source directory 2020-01-15 15:13:10 -10:00
translate-a64.h Allow page table bit to swap endianness. 2019-09-04 16:29:18 +01:00
translate-sve.c tcg: Search includes from the project root source directory 2020-01-15 15:13:10 -10:00
translate-vfp.inc.c target/arm: Handle trapping to EL2 of AArch32 VMRS instructions 2019-12-16 10:46:34 +00:00
translate.c tcg: Search includes from the project root source directory 2020-01-15 15:13:10 -10:00
translate.h target/arm: Handle AArch32 CP15 trapping via HSTR_EL2 2019-12-16 10:46:35 +00:00
vec_helper.c target/arm: Add helpers for FMLAL 2019-02-28 11:03:05 +00:00
vfp_helper.c target/arm: Handle trapping to EL2 of AArch32 VMRS instructions 2019-12-16 10:46:34 +00:00
vfp-uncond.decode target/arm: Convert VCVTA/VCVTN/VCVTP/VCVTM to decodetree 2019-06-13 15:14:04 +01:00
vfp.decode target/arm: Use vfp_expand_imm() for AArch32 VFP VMOV_imm 2019-06-17 15:14:19 +01:00