| Message ID | 20240122163607.459769-1-peter.maydell@linaro.org |
|---|---|
| Headers | show |
| Series | system: Fix handling of '-serial none -serial something' | expand |
On Mon, 22 Jan 2024 at 16:36, Peter Maydell <peter.maydell@linaro.org> wrote: > > (This patchset fixes a bug reported by Bohdan Kostiv at > https://lore.kernel.org/qemu-devel/CAA3Sv1LQ8yDUNLCB5WqLVZjsHffrU0uSbL_YYJW_m+Db2PhEeQ@mail.gmail.com/ > -- my patch 1 avoids a bug in his suggested change, and > patch 2 is new, improving the documentation.) > > Currently if the user passes multiple -serial options on the command > line, we mostly treat those as applying to the different serial > devices in order, so that for example > -serial stdio -serial file:filename > will connect the first serial port to stdio and the second to the > named file. > > The exception to this is the '-serial none' serial device type. This > means "don't allocate this serial device", but a bug means that > following -serial options are not correctly handled, so that > -serial none -serial stdio > has the unexpected effect that stdio is connected to the first serial > port, not the second. I'll take this series via target-arm.next. thanks -- PMM
(This patchset fixes a bug reported by Bohdan Kostiv at https://lore.kernel.org/qemu-devel/CAA3Sv1LQ8yDUNLCB5WqLVZjsHffrU0uSbL_YYJW_m+Db2PhEeQ@mail.gmail.com/ -- my patch 1 avoids a bug in his suggested change, and patch 2 is new, improving the documentation.) Currently if the user passes multiple -serial options on the command line, we mostly treat those as applying to the different serial devices in order, so that for example -serial stdio -serial file:filename will connect the first serial port to stdio and the second to the named file. The exception to this is the '-serial none' serial device type. This means "don't allocate this serial device", but a bug means that following -serial options are not correctly handled, so that -serial none -serial stdio has the unexpected effect that stdio is connected to the first serial port, not the second. This is a very long-standing bug that dates back at least as far as commit 998bbd74b9d81 from 2009. It's possible that some users have commandlines that mistakenly include a previously-redundant '-serial none'; those users can simply delete that option in order to produce a command line that has the same effect on both old and new QEMU. We can mention this in the release notes. Our documentation for -serial none and -serial null was also a bit lacking; I've provided a patch here which tries to improve it. thanks -- PMM Peter Maydell (2): system/vl.c: Fix handling of '-serial none -serial something' qemu-options.hx: Improve -serial option documentation system/vl.c | 22 +++++++++++++--------- qemu-options.hx | 14 +++++++++++--- 2 files changed, 24 insertions(+), 12 deletions(-)