[PATCH] rust: pl011: Allow NULL chardev argument to pl011_create()

Peter Maydell posted 1 patch 8 months, 1 week ago
Patches applied successfully (tree, apply log)
git fetch https://github.com/patchew-project/qemu tags/patchew/20250307190051.3274226-1-peter.maydell@linaro.org
Maintainers: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
rust/hw/char/pl011/src/device.rs | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
[PATCH] rust: pl011: Allow NULL chardev argument to pl011_create()
Posted by Peter Maydell 8 months, 1 week ago
It's valid for the caller to pass a NULL chardev to pl011_create();
this means "don't set the chardev property on the device", which
in turn means "act like there's no chardev". All the chardev
frontend APIs (in C, at least) accept a NULL pointer to mean
"do nothing".

This fixes some failures in 'make check-functional' when Rust support
is enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
This is my first Rust related patch for QEMU, so I've
probably got something wrong here :-)
---
 rust/hw/char/pl011/src/device.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/rust/hw/char/pl011/src/device.rs b/rust/hw/char/pl011/src/device.rs
index d0857b470c9..8098f762f4b 100644
--- a/rust/hw/char/pl011/src/device.rs
+++ b/rust/hw/char/pl011/src/device.rs
@@ -713,10 +713,12 @@ pub fn post_load(&self, _version_id: u32) -> Result<(), ()> {
     // SAFETY: The callers promise that they have owned references.
     // They do not gift them to pl011_create, so use `Owned::from`.
     let irq = unsafe { Owned::<IRQState>::from(&*irq) };
-    let chr = unsafe { Owned::<Chardev>::from(&*chr) };
 
     let dev = PL011State::new();
-    dev.prop_set_chr("chardev", &chr);
+    if !chr.is_null() {
+        let chr = unsafe { Owned::<Chardev>::from(&*chr) };
+        dev.prop_set_chr("chardev", &chr);
+    }
     dev.sysbus_realize();
     dev.mmio_map(0, addr);
     dev.connect_irq(0, &irq);
-- 
2.43.0
Re: [PATCH] rust: pl011: Allow NULL chardev argument to pl011_create()
Posted by Paolo Bonzini 8 months, 1 week ago
> This is my first Rust related patch for QEMU, so I've
> probably got something wrong here :-)

No no, that was all good!  Applied, thanks.

Paolo
Re: [PATCH] rust: pl011: Allow NULL chardev argument to pl011_create()
Posted by Philippe Mathieu-Daudé 8 months, 1 week ago
On 7/3/25 20:00, Peter Maydell wrote:
> It's valid for the caller to pass a NULL chardev to pl011_create();
> this means "don't set the chardev property on the device", which
> in turn means "act like there's no chardev". All the chardev
> frontend APIs (in C, at least) accept a NULL pointer to mean
> "do nothing".
> 
> This fixes some failures in 'make check-functional' when Rust support
> is enabled.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
> This is my first Rust related patch for QEMU, so I've
> probably got something wrong here :-)
> ---
>   rust/hw/char/pl011/src/device.rs | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/rust/hw/char/pl011/src/device.rs b/rust/hw/char/pl011/src/device.rs
> index d0857b470c9..8098f762f4b 100644
> --- a/rust/hw/char/pl011/src/device.rs
> +++ b/rust/hw/char/pl011/src/device.rs
> @@ -713,10 +713,12 @@ pub fn post_load(&self, _version_id: u32) -> Result<(), ()> {
>       // SAFETY: The callers promise that they have owned references.
>       // They do not gift them to pl011_create, so use `Owned::from`.
>       let irq = unsafe { Owned::<IRQState>::from(&*irq) };
> -    let chr = unsafe { Owned::<Chardev>::from(&*chr) };
>   
>       let dev = PL011State::new();
> -    dev.prop_set_chr("chardev", &chr);
> +    if !chr.is_null() {
> +        let chr = unsafe { Owned::<Chardev>::from(&*chr) };
> +        dev.prop_set_chr("chardev", &chr);
> +    }
>       dev.sysbus_realize();
>       dev.mmio_map(0, addr);
>       dev.connect_irq(0, &irq);

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>