Daniel Borkmann <daniel@xxxxxxxxxxxxx> writes: > On 5/28/20 2:23 PM, Michael Ellerman wrote: >> Petr Mladek <pmladek@xxxxxxxx> writes: >>> On Thu 2020-05-28 11:03:43, Michael Ellerman wrote: >>>> Petr Mladek <pmladek@xxxxxxxx> writes: >>>>> The commit 0ebeea8ca8a4d1d453a ("bpf: Restrict bpf_probe_read{, str}() only >>>>> to archs where they work") caused that bpf_probe_read{, str}() functions >>>>> were not longer available on architectures where the same logical address >>>>> might have different content in kernel and user memory mapping. These >>>>> architectures should use probe_read_{user,kernel}_str helpers. >>>>> >>>>> For backward compatibility, the problematic functions are still available >>>>> on architectures where the user and kernel address spaces are not >>>>> overlapping. This is defined CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE. >>>>> >>>>> At the moment, these backward compatible functions are enabled only >>>>> on x86_64, arm, and arm64. Let's do it also on powerpc that has >>>>> the non overlapping address space as well. >>>>> >>>>> Signed-off-by: Petr Mladek <pmladek@xxxxxxxx> >>>> >>>> This seems like it should have a Fixes: tag and go into v5.7? >>> >>> Good point: >>> >>> Fixes: commit 0ebeea8ca8a4d1d4 ("bpf: Restrict bpf_probe_read{, str}() only to archs where they work") >>> >>> And yes, it should ideally go into v5.7 either directly or via stable. >>> >>> Should I resend the patch with Fixes and >>> Cc: stable@xxxxxxxxxxxxxxx #v45.7 lines, please? >> >> If it goes into v5.7 then it doesn't need a Cc: stable, and I guess a >> Fixes: tag is nice to have but not so important as it already mentions >> the commit that caused the problem. So a resend probably isn't >> necessary. >> >> Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> >> >> Daniel can you pick this up, or should I? > > Yeah I'll take it into bpf tree for v5.7. Thanks. cheers