| Message ID | 20200403132622.130394-7-npiggin@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | powerpc/64: machine check and system reset fixes | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (d0c12846a3a24cd6d68b608c866712bc7e471634) |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 13 lines checked |
| snowpatch_ozlabs/needsstable | success | Patch has no Fixes tags |
Le 03/04/2020 à 15:26, Nicholas Piggin a écrit : > This was discovered developing qemu fwnmi sreset support. This > off-by-one bug means the last 16 bytes of the rtas area can not > be used for a 16 byte save area. > > It's not a serious bug, and QEMU implementation has to retain a > workaround for old kernels, but it's good to tighten it. > > Acked-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> > --- > arch/powerpc/platforms/pseries/ras.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c > index c74d5e740922..9a37bda47468 100644 > --- a/arch/powerpc/platforms/pseries/ras.c > +++ b/arch/powerpc/platforms/pseries/ras.c > @@ -395,10 +395,11 @@ static irqreturn_t ras_error_interrupt(int irq, void *dev_id) > /* > * Some versions of FWNMI place the buffer inside the 4kB page starting at > * 0x7000. Other versions place it inside the rtas buffer. We check both. > + * Minimum size of the buffer is 16 bytes. > */ > #define VALID_FWNMI_BUFFER(A) \ > - ((((A) >= 0x7000) && ((A) < 0x7ff0)) || \ > - (((A) >= rtas.base) && ((A) < (rtas.base + rtas.size - 16)))) > + ((((A) >= 0x7000) && ((A) <= 0x8000 - 16)) || \ > + (((A) >= rtas.base) && ((A) <= (rtas.base + rtas.size - 16)))) Why not just change < to <= and leave the 0x7ff0 ? > > static inline struct rtas_error_log *fwnmi_get_errlog(void) > { > Christophe
diff --git a/arch/powerpc/platforms/pseries/ras.c b/arch/powerpc/platforms/pseries/ras.c index c74d5e740922..9a37bda47468 100644 --- a/arch/powerpc/platforms/pseries/ras.c +++ b/arch/powerpc/platforms/pseries/ras.c @@ -395,10 +395,11 @@ static irqreturn_t ras_error_interrupt(int irq, void *dev_id) /* * Some versions of FWNMI place the buffer inside the 4kB page starting at * 0x7000. Other versions place it inside the rtas buffer. We check both. + * Minimum size of the buffer is 16 bytes. */ #define VALID_FWNMI_BUFFER(A) \ - ((((A) >= 0x7000) && ((A) < 0x7ff0)) || \ - (((A) >= rtas.base) && ((A) < (rtas.base + rtas.size - 16)))) + ((((A) >= 0x7000) && ((A) <= 0x8000 - 16)) || \ + (((A) >= rtas.base) && ((A) <= (rtas.base + rtas.size - 16)))) static inline struct rtas_error_log *fwnmi_get_errlog(void) {