| Message ID | 20230224023632.6840-1-weichen.chen@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v1,1/1] pstore/ram: Fix crash when setting number of cpus to an odd number | expand |
On 23/02/2023 23:36, Weichen Chen wrote: > When the number of cpu cores is adjusted to 7 or other odd numbers, > the zone size will become an odd number. > The address of the zone will become: > addr of zone0 = BASE > addr of zone1 = BASE + zone_size > addr of zone2 = BASE + zone_size*2 > ... > The address of zone1/3/5/7 will be mapped to non-alignment va. > Eventually crashes will occur when accessing these va. > > So, use ALIGN_DOWN() to make sure the zone size is even > to avoid this bug. > > Signed-off-by: Weichen Chen <weichen.chen@mediatek.com> > --- > fs/pstore/ram.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c > index ade66dbe5f39..fc57ac97e506 100644 > --- a/fs/pstore/ram.c > +++ b/fs/pstore/ram.c > @@ -528,6 +528,7 @@ static int ramoops_init_przs(const char *name, > } > > zone_sz = mem_sz / *cnt; > + zone_sz = ALIGN_DOWN(zone_sz, 2); > if (!zone_sz) { > dev_err(dev, "%s zone size == 0\n", name); > goto fail; Thanks for resending! Feel free to add my: Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Cheers, Guilherme
On Fri, 2023-02-24 at 10:36 +0800, Weichen Chen wrote: > When the number of cpu cores is adjusted to 7 or other odd numbers, > the zone size will become an odd number. > The address of the zone will become: > addr of zone0 = BASE > addr of zone1 = BASE + zone_size > addr of zone2 = BASE + zone_size*2 > ... > The address of zone1/3/5/7 will be mapped to non-alignment va. > Eventually crashes will occur when accessing these va. > > So, use ALIGN_DOWN() to make sure the zone size is even > to avoid this bug. > > Signed-off-by: Weichen Chen <weichen.chen@mediatek.com> > --- > fs/pstore/ram.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c > index ade66dbe5f39..fc57ac97e506 100644 > --- a/fs/pstore/ram.c > +++ b/fs/pstore/ram.c > @@ -528,6 +528,7 @@ static int ramoops_init_przs(const char *name, > } > > zone_sz = mem_sz / *cnt; > + zone_sz = ALIGN_DOWN(zone_sz, 2); > if (!zone_sz) { > dev_err(dev, "%s zone size == 0\n", name); > goto fail; Might want to Cc this to the stable mailing list.
On 24/02/2023 05:00, Guilherme G. Piccoli wrote: > On 23/02/2023 23:36, Weichen Chen wrote: >> When the number of cpu cores is adjusted to 7 or other odd numbers, >> the zone size will become an odd number. >> The address of the zone will become: >> addr of zone0 = BASE >> addr of zone1 = BASE + zone_size >> addr of zone2 = BASE + zone_size*2 >> ... >> The address of zone1/3/5/7 will be mapped to non-alignment va. >> Eventually crashes will occur when accessing these va. >> >> So, use ALIGN_DOWN() to make sure the zone size is even >> to avoid this bug. >> >> Signed-off-by: Weichen Chen <weichen.chen@mediatek.com> >> --- >> fs/pstore/ram.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c >> index ade66dbe5f39..fc57ac97e506 100644 >> --- a/fs/pstore/ram.c >> +++ b/fs/pstore/ram.c >> @@ -528,6 +528,7 @@ static int ramoops_init_przs(const char *name, >> } >> >> zone_sz = mem_sz / *cnt; >> + zone_sz = ALIGN_DOWN(zone_sz, 2); >> if (!zone_sz) { >> dev_err(dev, "%s zone size == 0\n", name); >> goto fail; > > Thanks for resending! Feel free to add my: > > Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> > Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com> I gave that yesterday, but Weichen Chen seems to have forgotten about it. Regards, Matthias
On Fri, 24 Feb 2023 10:36:32 +0800, Weichen Chen wrote: > When the number of cpu cores is adjusted to 7 or other odd numbers, > the zone size will become an odd number. > The address of the zone will become: > addr of zone0 = BASE > addr of zone1 = BASE + zone_size > addr of zone2 = BASE + zone_size*2 > ... > The address of zone1/3/5/7 will be mapped to non-alignment va. > Eventually crashes will occur when accessing these va. > > [...] Applied to for-next/pstore, thanks! [1/1] pstore/ram: Fix crash when setting number of cpus to an odd number https://git.kernel.org/kees/c/1d49dee6b691 Take care,
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index ade66dbe5f39..fc57ac97e506 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -528,6 +528,7 @@ static int ramoops_init_przs(const char *name, } zone_sz = mem_sz / *cnt; + zone_sz = ALIGN_DOWN(zone_sz, 2); if (!zone_sz) { dev_err(dev, "%s zone size == 0\n", name); goto fail;
When the number of cpu cores is adjusted to 7 or other odd numbers, the zone size will become an odd number. The address of the zone will become: addr of zone0 = BASE addr of zone1 = BASE + zone_size addr of zone2 = BASE + zone_size*2 ... The address of zone1/3/5/7 will be mapped to non-alignment va. Eventually crashes will occur when accessing these va. So, use ALIGN_DOWN() to make sure the zone size is even to avoid this bug. Signed-off-by: Weichen Chen <weichen.chen@mediatek.com> --- fs/pstore/ram.c | 1 + 1 file changed, 1 insertion(+)