32-bit Thumb-2 breakpoints

Nicolas Pitre nico at fluxnic.net
Wed Feb 3 10:35:38 EST 2010

On Wed, 3 Feb 2010, Daniel Jacobowitz wrote:

> On Wed, Feb 03, 2010 at 04:02:40PM +0100, Matthieu CASTET wrote:
> > An annoying things about software breakpoints is that gdb doesn't
> > understand arm kernel helper (for atomic operation/tls). And when it try
> > to set breakpoint here it fails...
> This is fixed in current GDB; it knows how to step out of the helper
> page automatically.  If you're still seeing a problem with GDB 7.0,
> could you file a bug?
> On a related note, it would be Very Helpful(TM) if someone would
> implement read-only access to the helper page via ptrace!  Not as
> helpful as a visible vDSO with symbol names would be, but it would
> still make things a lot easier.

Why?  Can't you just access it directly straight from gdb's own address 
space?  This page is the same for all tasks on the system.


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