Hi Will, thx for having a look. Am 08.05.2013 10:57, schrieb Will Deacon:> Hi Andre, > > On Tue, May 07, 2013 at 09:51:00PM +0100, André Hentschel wrote: >> From: =?UTF-8?q?Andr=C3=A9=20Hentschel?= <nerv@xxxxxxxxxxx> > > Might just be my mailer, but you should check that your name is intact here > otherwise the git log will be mangled. That's for my acute accent and already worked with my first linux patch, it's git generated. >> Since commit 6a1c53124aa1 the user writeable TLS register was zeroed to >> prevent it from being used as a covert channel between two tasks. >> >> There are more and more applications coming to WinRT, Wine could support them, >> but mostly they expect to have the thread environment block (TEB) in TPIDRURW. >> >> This patch preserves that register per thread instead of clearing it. >> Unlike the TPIDRURO, which is already switched, the TPIDRURW >> can be updated from userspace so needs careful treatment in the case that we >> modify TPIDRURW and call fork(). To avoid this we must always read >> TPIDRURW in copy_thread. >> >> Signed-off-by: André Hentschel <nerv@xxxxxxxxxxx> >> Signed-off-by: Will Deacon <will.deacon@xxxxxxx> >> Signed-off-by: Jonathan Austin <jonathan.austin@xxxxxxx> > > [...] > >> diff --git a/arch/arm/include/asm/tls.h b/arch/arm/include/asm/tls.h >> index 73409e6..22756ab 100644 >> --- a/arch/arm/include/asm/tls.h >> +++ b/arch/arm/include/asm/tls.h >> @@ -2,27 +2,30 @@ >> #define __ASMARM_TLS_H >> >> #ifdef __ASSEMBLY__ >> - .macro set_tls_none, tp, tmp1, tmp2 >> +#include <asm/asm-offsets.h> >> + .macro switch_tls_none, base, tp, tpuser, tmp1, tmp2 >> .endm >> >> - .macro set_tls_v6k, tp, tmp1, tmp2 >> + .macro switch_tls_v6k, base, tp, tpuser, tmp1, tmp2 >> + mrc p15, 0, \tmp2, c13, c0, 2 @ get the user r/w register >> mcr p15, 0, \tp, c13, c0, 3 @ set TLS register >> - mov \tmp1, #0 >> - mcr p15, 0, \tmp1, c13, c0, 2 @ clear user r/w TLS register >> + mcr p15, 0, \tpuser, c13, c0, 2 @ and the user r/w register >> + strne \tmp2, [\base, #TI_TP_VALUE + 4] @ save it > > Why is this conditional? Seems like a copy&paste one, i'll send a v4 -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
