On 10/6/25 14:56, Daniel P. Berrangé wrote:
On Tue, Jun 10, 2025 at 02:49:02PM +0200, Philippe Mathieu-Daudé wrote:
On 10/6/25 14:36, Daniel P. Berrangé wrote:
This series is an extension of Stefan's proposal:
https://lists.nongnu.org/archive/html/qemu-devel/2025-06/msg00736.html
It used '-Wframe-larger-than=4096' to identify all code locations
with more than 4k on the stack. Any locations in the I/O paths
were chosen to avoid automatic zero-init, to eliminate the performance
overhead of the automatic initialization.
Should we eventually add it to our default CFLAGS?
You mean as a way to impose a hard limit on stack frame size ?
Yes, we could use -Wframe-larger-than=50000 for this release, then
aim to reduce by 5/10k every release until some reasonable limit...
FWIW, the VNC server is biggest at 100kb, but we have a large
number of other big frames - here's a sorted list of frame
sizes vs frequency
1 103696
2 69664
46 49184
4 42608
23 32880
23 32864
