| commit | 34b0311d0eb906bd801cc1e9a329ed211b81496f | |
| author | Thomas Martitz <kugel@rockbox.org> | |
| Fri, 13 Jan 2012 08:47:01 +0000 (13 09:47 +0100) | ||
| committer | Thomas Martitz <kugel@rockbox.org> | |
| Sat, 21 Jan 2012 17:39:19 +0000 (21 18:39 +0100) | ||
| tree | b76d82b8ecb94aab048c58d2b6f3c23b57e15b7a | treesnapshot (tar.gz zip) |
| parent | 109084d5cbaeee26373ecf1b765d9507ccbbe63e | commitdiff |
hosted/pcm/alsa: Use alternate signal stack for the async callback.
Signals are by default executed on the user stack, i.e. the stack of
the currently active thread. This has two problems:
1) The stack size of the current stack is likely insufficient (unless
using sigaltstack threads) because our stack sizes are normally
below MINSIGSTKSIZE which is needed to deliver a signal.
2) Some of our asm code does nasty tricks with the stack pointer. When a
signal comes in during this bad things can happen, e.g. random memory
being overwritten or simply a crash.
Using a well defined stack fixes this. This is comparable with the
separate irq stack on native targets.
Signals are by default executed on the user stack, i.e. the stack of
the currently active thread. This has two problems:
1) The stack size of the current stack is likely insufficient (unless
using sigaltstack threads) because our stack sizes are normally
below MINSIGSTKSIZE which is needed to deliver a signal.
2) Some of our asm code does nasty tricks with the stack pointer. When a
signal comes in during this bad things can happen, e.g. random memory
being overwritten or simply a crash.
Using a well defined stack fixes this. This is comparable with the
separate irq stack on native targets.
| firmware/target/hosted/pcm-alsa.c | diffblobblamehistory |