On 11/05/16 14:55, Rashmica Gupta wrote:
> The same logic for tm_abort appears twice, so pull it out into a
> function.
>
> Signed-off-by: Rashmica Gupta <rashm...@gmail.com>
> ---
> arch/powerpc/mm/hash_utils_64.c | 47
> ++++++++++++++++++-----------------------
> 1 file changed, 21 insertions(+), 26 deletions(-)
>
> diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
> index 7635b1c6b5da..1cef8f5aee9b 100644
> --- a/arch/powerpc/mm/hash_utils_64.c
> +++ b/arch/powerpc/mm/hash_utils_64.c
> @@ -1318,6 +1318,25 @@ out_exit:
> local_irq_restore(flags);
> }
>
> +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
> + /* Transactions are not aborted by tlbiel, only tlbie.
> + * Without, syncing a page back to a block device w/ PIO could pick up
> + * transactional data (bad!) so we force an abort here. Before the
> + * sync the page will be made read-only, which will flush_hash_page.
> + * BIG ISSUE here: if the kernel uses a page from userspace without
> + * unmapping it first, it may see the speculated version.
> + */
> +static inline void abort_tm(int local)
> +{
> + if (local && cpu_has_feature(CPU_FTR_TM) &&
> + current->thread.regs &&
> + MSR_TM_ACTIVE(current->thread.regs->msr)) {
> + tm_enable();
> + tm_abort(TM_CAUSE_TLBI);
> + }
> +}
While your at this do
#else
static inline void abort_tm(int local)
{
}
> +#endif
> +
> /* WARNING: This is called from hash_low_64.S, if you change this prototype,
> * do not forget to update the assembly call site !
> */
> @@ -1344,19 +1363,7 @@ void flush_hash_page(unsigned long vpn, real_pte_t
> pte, int psize, int ssize,
> } pte_iterate_hashed_end();
>
> #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
Then remove these extra #ifdef
> - /* Transactions are not aborted by tlbiel, only tlbie.
> - * Without, syncing a page back to a block device w/ PIO could pick up
> - * transactional data (bad!) so we force an abort here. Before the
> - * sync the page will be made read-only, which will flush_hash_page.
> - * BIG ISSUE here: if the kernel uses a page from userspace without
> - * unmapping it first, it may see the speculated version.
> - */
> - if (local && cpu_has_feature(CPU_FTR_TM) &&
> - current->thread.regs &&
> - MSR_TM_ACTIVE(current->thread.regs->msr)) {
> - tm_enable();
> - tm_abort(TM_CAUSE_TLBI);
> - }
> + abort_tm(local);
> #endif
> }
>
> @@ -1415,19 +1422,7 @@ void flush_hash_hugepage(unsigned long vsid, unsigned
> long addr,
> }
> tm_abort:
> #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
Then remove these extra #ifdef
> - /* Transactions are not aborted by tlbiel, only tlbie.
> - * Without, syncing a page back to a block device w/ PIO could pick up
> - * transactional data (bad!) so we force an abort here. Before the
> - * sync the page will be made read-only, which will flush_hash_page.
> - * BIG ISSUE here: if the kernel uses a page from userspace without
> - * unmapping it first, it may see the speculated version.
> - */
> - if (local && cpu_has_feature(CPU_FTR_TM) &&
> - current->thread.regs &&
> - MSR_TM_ACTIVE(current->thread.regs->msr)) {
> - tm_enable();
> - tm_abort(TM_CAUSE_TLBI);
> - }
> + abort_tm(local);
> #endif
> return;
> }
>
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