Re: [PATCH 1/3] target/arm: Use CONFIG_SEMIHOSTING instead of TCG for semihosting

[Paolo Bonzini]

On 5/3/23 21:38, Fabiano Rosas wrote:
> When building --without-default-devices, the semihosting code will not
> be available, so check the proper config.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>

for this change; however, there are two more related issues:

1) you still want to leave out the code if !TCG, because KVM is not able
to exit to userspace on semihosting calls as far as I understand

2) I am not sure why CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y appears in
config/targets/{arm,riscv32,riscv64}-softmmu/default.mak.

Putting things together you also need something like

diff --git a/semihosting/Kconfig b/semihosting/Kconfig
index eaf3a20ef5b2..671020a33426 100644
--- a/semihosting/Kconfig
+++ b/semihosting/Kconfig
@@ -4,4 +4,5 @@ config SEMIHOSTING
 
 config ARM_COMPATIBLE_SEMIHOSTING
        bool
+       default y if (ARM && TCG) || RISCV32 || RISCV64
        select SEMIHOSTING
diff --git a/configs/devices/arm-softmmu/default.mak 
b/configs/devices/arm-softmmu/default.mak
index 1b49a7830c7e..5e7a17d05bf8 100644
--- a/configs/devices/arm-softmmu/default.mak
+++ b/configs/devices/arm-softmmu/default.mak
@@ -41,5 +41,4 @@ CONFIG_FSL_IMX25=y
 CONFIG_FSL_IMX7=y
 CONFIG_FSL_IMX6UL=y
 CONFIG_SEMIHOSTING=y
-CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
 CONFIG_ALLWINNER_H3=y
diff --git a/configs/devices/riscv32-softmmu/default.mak 
b/configs/devices/riscv32-softmmu/default.mak
index d847bd5692ec..94a236c9c25b 100644
--- a/configs/devices/riscv32-softmmu/default.mak
+++ b/configs/devices/riscv32-softmmu/default.mak
@@ -3,8 +3,6 @@
 # Uncomment the following lines to disable these optional devices:
 #
 #CONFIG_PCI_DEVICES=n
-CONFIG_SEMIHOSTING=y
-CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
 
 # Boards:
 #
diff --git a/configs/devices/riscv64-softmmu/default.mak 
b/configs/devices/riscv64-softmmu/default.mak
index bc69301fa4a6..3f6805944849 100644
--- a/configs/devices/riscv64-softmmu/default.mak
+++ b/configs/devices/riscv64-softmmu/default.mak
@@ -3,8 +3,6 @@
 # Uncomment the following lines to disable these optional devices:
 #
 #CONFIG_PCI_DEVICES=n
-CONFIG_SEMIHOSTING=y
-CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
 
 # Boards:
 #

Paolo

> Fixes: 29d9efca16 ("arm/Kconfig: Do not build TCG-only boards on a KVM-only 
> build")
> Signed-off-by: Fabiano Rosas<farosas@suse.de>
> ---
>   target/arm/helper.c       | 4 ++--
>   target/arm/tcg/m_helper.c | 2 +-
>   2 files changed, 3 insertions(+), 3 deletions(-)