On Wed, Jul 12, 2017 at 09:18:26PM +0200, Richard Weinberger wrote: > Thomas, > > Am 12.07.2017 um 17:11 schrieb Thomas Meyer: > > Am 10.07.2017 9:06 nachm. schrieb Richard Weinberger <rich...@nod.at>: > > > > Thomas, > > > > Am 10.07.2017 um 00:33 schrieb Thomas Meyer: > > > Hard code max size. Taken from > > > > > https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=gdb/common/x86-xstate.h > > > > > > v3: use static fp_regs for get_skas_faultinfo > > > > > > Signed-off-by: Thomas Meyer <tho...@m3y3r.de> > > > --- > > > arch/um/os-Linux/skas/process.c | 7 ++++--- > > > arch/x86/um/os-Linux/registers.c | 18 ++++++++++++------ > > > arch/x86/um/user-offsets.c | 2 +- > > > 3 files changed, 17 insertions(+), 10 deletions(-) > > > > > > diff --git a/arch/um/os-Linux/skas/process.c > > b/arch/um/os-Linux/skas/process.c > > > index 03b3c4cc7735..b5fdef795985 100644 > > > --- a/arch/um/os-Linux/skas/process.c > > > +++ b/arch/um/os-Linux/skas/process.c > > > @@ -88,12 +88,13 @@ void wait_stub_done(int pid) > > > > > > extern unsigned long current_stub_stack(void); > > > > > > +static unsigned long skas_faultinfo_fpregs[FP_SIZE]; > > > + > > > > Uhmm, are you sure that this does not race with other userspace() > > instances? > > > > Oh, is it really possible that a task gets schedule while we are in > > userspace signal handling from ptrace? > > I hoped that you'd double check. ;)
I just did write a little test program, which seems to survive this patch. Please have a look at this test program. As far as I understand the problem, the test program should cover above test case. Feel free to have a look at it: https://github.com/thomasmey/xmm-test/ > From my knowledge it is not possible, but this code was not written by me and > UML internal > semantics are more than tricky. > Let's postpone this patch for -rc2 and check again. > > > Another question: when malloc a memory area in userspace: when does a > > userspace process end in userspace function!? Where would you free the > > malloced memory? > > It ends via handle_trap() when userspac does an exit syscall. > I agree this is tricky to catch and needs more effort. Ah, okay, that makes sense! > > Thanks, > //richard ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
