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| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-16 10:33:54 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-16 10:33:54 +0200 |
| commit | e4ed2b5370a2df2b1feeb970904d2f7761c241c9 (patch) | |
| tree | 852b17dcc8ed1ca8f35771e8f06d660bdfc51804 /arch/powerpc/kernel/signal_64.c | |
| parent | 4fcae770f3027abefd952c5d511ac6299828865a (diff) | |
| parent | 33d930e59a98fa10a0db9f56c7fa2f21a4aef9b9 (diff) | |
| download | linux-e4ed2b5370a2df2b1feeb970904d2f7761c241c9.tar.gz linux-e4ed2b5370a2df2b1feeb970904d2f7761c241c9.tar.bz2 linux-e4ed2b5370a2df2b1feeb970904d2f7761c241c9.zip | |
Merge 4.14-rc5 into usb-next
We want the USB fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/powerpc/kernel/signal_64.c')
| -rw-r--r-- | arch/powerpc/kernel/signal_64.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c index c83c115858c1..b2c002993d78 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -452,9 +452,20 @@ static long restore_tm_sigcontexts(struct task_struct *tsk, if (MSR_TM_RESV(msr)) return -EINVAL; - /* pull in MSR TM from user context */ + /* pull in MSR TS bits from user context */ regs->msr = (regs->msr & ~MSR_TS_MASK) | (msr & MSR_TS_MASK); + /* + * Ensure that TM is enabled in regs->msr before we leave the signal + * handler. It could be the case that (a) user disabled the TM bit + * through the manipulation of the MSR bits in uc_mcontext or (b) the + * TM bit was disabled because a sufficient number of context switches + * happened whilst in the signal handler and load_tm overflowed, + * disabling the TM bit. In either case we can end up with an illegal + * TM state leading to a TM Bad Thing when we return to userspace. + */ + regs->msr |= MSR_TM; + /* pull in MSR LE from user context */ regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE); |