| Message ID | 20200325103410.157573-6-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| State | Superseded |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 | warning | Failed to apply on branch powerpc/merge (a87b93bdf800a4d7a42d95683624a4516e516b4f) |
| snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch powerpc/next (59ed2adf393109c56d383e568f2e57bb5ad6d901) |
| snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch linus/master (76ccd234269bd05debdbc12c96eafe62dd9a6180) |
| snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch powerpc/fixes (1d0c32ec3b860a32df593a22bad0d1dbc5546a59) |
| snowpatch_ozlabs/apply_patch | warning | Failed to apply on branch linux-next (bfd7a248502373da8b1c8eb0e811fdb19cc3f8b6) |
| snowpatch_ozlabs/apply_patch | fail | Failed to apply to any branch |
On 2020-03-25 20:34:03 Wed, Nicholas Piggin wrote: > 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. > > 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. Acked-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Thanks, -Mahesh. > */ > #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) > { > -- > 2.23.0 >
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) {
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. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/platforms/pseries/ras.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)