| Message ID | 20190501092841.9026-7-rasmus.villemoes@prevas.dk (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | [v2,1/6] soc/fsl/qe: qe.c: drop useless static qualifier | expand |
Le 01/05/2019 à 11:29, Rasmus Villemoes a écrit : > The comment "No QE ever has fewer than 28 SNUMs" is false; e.g. the > MPC8309 has 14. The code path returning -EINVAL is also a recipe for > instant disaster, since the caller (qe_snums_init) uncritically > assigns the return value to the unsigned qe_num_of_snum, and would > thus proceed to attempt to copy 4GB from snum_init_46[] to the snum[] > array. > > So fold the handling of the legacy fsl,qe-num-snums into > qe_snums_init, and make sure we do not end up using the snum_init_46 > array in cases other than the two where we know it makes sense. > > Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> > --- > drivers/soc/fsl/qe/qe.c | 46 ++++++++++++++--------------------------- > 1 file changed, 16 insertions(+), 30 deletions(-) > > diff --git a/drivers/soc/fsl/qe/qe.c b/drivers/soc/fsl/qe/qe.c > index 325d689cbf5c..276d7d78ebfc 100644 > --- a/drivers/soc/fsl/qe/qe.c > +++ b/drivers/soc/fsl/qe/qe.c > @@ -308,24 +308,33 @@ static void qe_snums_init(void) > int i; > > bitmap_zero(snum_state, QE_NUM_OF_SNUM); > + qe_num_of_snum = 28; /* The default number of snum for threads is 28 */ > qe = qe_get_device_node(); > if (qe) { > i = of_property_read_variable_u8_array(qe, "fsl,qe-snums", > snums, 1, QE_NUM_OF_SNUM); > - of_node_put(qe); > if (i > 0) { > + of_node_put(qe); > qe_num_of_snum = i; > return; > } > + /* > + * Fall back to legacy binding of using the value of > + * fsl,qe-num-snums to choose one of the static arrays > + * above. > + */ > + of_property_read_u32(qe, "fsl,qe-num-snums", &qe_num_of_snum); > + of_node_put(qe); > } > > - qe_num_of_snum = qe_get_num_of_snums(); > - > - if (qe_num_of_snum == 76) > + if (qe_num_of_snum == 76) { > snum_init = snum_init_76; > - else > + } else if (qe_num_of_snum == 28 || qe_num_of_snum == 46) { > snum_init = snum_init_46; > - > + } else { > + pr_err("QE: unsupported value of fsl,qe-num-snums: %u\n", qe_num_of_snum); > + return; > + } > memcpy(snums, snum_init, qe_num_of_snum); > } > > @@ -641,30 +650,7 @@ EXPORT_SYMBOL(qe_get_num_of_risc); > > unsigned int qe_get_num_of_snums(void) > { > - struct device_node *qe; > - int size; > - unsigned int num_of_snums; > - const u32 *prop; > - > - num_of_snums = 28; /* The default number of snum for threads is 28 */ > - qe = qe_get_device_node(); > - if (!qe) > - return num_of_snums; > - > - prop = of_get_property(qe, "fsl,qe-num-snums", &size); > - if (prop && size == sizeof(*prop)) { > - num_of_snums = *prop; > - if ((num_of_snums < 28) || (num_of_snums > QE_NUM_OF_SNUM)) { > - /* No QE ever has fewer than 28 SNUMs */ > - pr_err("QE: number of snum is invalid\n"); > - of_node_put(qe); > - return -EINVAL; > - } > - } > - > - of_node_put(qe); > - > - return num_of_snums; > + return qe_num_of_snum; > } > EXPORT_SYMBOL(qe_get_num_of_snums); > >
On 2019/5/1 17:29, Rasmus Villemoes <rasmus.villemoes@prevas.dk> wrote: > -----Original Message----- > From: Rasmus Villemoes <rasmus.villemoes@prevas.dk> > Sent: 2019年5月1日 17:29 > To: devicetree@vger.kernel.org; Qiang Zhao <qiang.zhao@nxp.com>; Leo Li > <leoyang.li@nxp.com> > Cc: linuxppc-dev@lists.ozlabs.org; linux-arm-kernel@lists.infradead.org; > linux-kernel@vger.kernel.org; Rob Herring <robh+dt@kernel.org>; Scott Wood > <oss@buserror.net>; Christophe Leroy <christophe.leroy@c-s.fr>; Mark > Rutland <mark.rutland@arm.com>; Rasmus Villemoes > <Rasmus.Villemoes@prevas.se> > Subject: [PATCH v2 6/6] soc/fsl/qe: qe.c: fold qe_get_num_of_snums into > qe_snums_init > > The comment "No QE ever has fewer than 28 SNUMs" is false; e.g. the > MPC8309 has 14. The code path returning -EINVAL is also a recipe for instant > disaster, since the caller (qe_snums_init) uncritically assigns the return value to > the unsigned qe_num_of_snum, and would thus proceed to attempt to copy > 4GB from snum_init_46[] to the snum[] array. > > So fold the handling of the legacy fsl,qe-num-snums into qe_snums_init, and > make sure we do not end up using the snum_init_46 array in cases other than > the two where we know it makes sense. > > Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> > --- Reviewed-by: Qiang Zhao <qiang.zhao@nxp.com> > drivers/soc/fsl/qe/qe.c | 46 ++++++++++++++--------------------------- > 1 file changed, 16 insertions(+), 30 deletions(-) > > diff --git a/drivers/soc/fsl/qe/qe.c b/drivers/soc/fsl/qe/qe.c index > 325d689cbf5c..276d7d78ebfc 100644 > --- a/drivers/soc/fsl/qe/qe.c > +++ b/drivers/soc/fsl/qe/qe.c > @@ -308,24 +308,33 @@ static void qe_snums_init(void) > int i; > > bitmap_zero(snum_state, QE_NUM_OF_SNUM); > + qe_num_of_snum = 28; /* The default number of snum for threads > + is 28 */ > qe = qe_get_device_node(); > if (qe) { > i = of_property_read_variable_u8_array(qe, "fsl,qe-snums", > snums, 1, > QE_NUM_OF_SNUM); > - of_node_put(qe); > if (i > 0) { > + of_node_put(qe); > qe_num_of_snum = i; > return; > } > + /* > + * Fall back to legacy binding of using the value of > + * fsl,qe-num-snums to choose one of the static arrays > + * above. > + */ > + of_property_read_u32(qe, "fsl,qe-num-snums", > &qe_num_of_snum); > + of_node_put(qe); > } > > - qe_num_of_snum = qe_get_num_of_snums(); > - > - if (qe_num_of_snum == 76) > + if (qe_num_of_snum == 76) { > snum_init = snum_init_76; > - else > + } else if (qe_num_of_snum == 28 || qe_num_of_snum == 46) { > snum_init = snum_init_46; > - > + } else { > + pr_err("QE: unsupported value of fsl,qe-num-snums: %u\n", > qe_num_of_snum); > + return; > + } > memcpy(snums, snum_init, qe_num_of_snum); } > > @@ -641,30 +650,7 @@ EXPORT_SYMBOL(qe_get_num_of_risc); > > unsigned int qe_get_num_of_snums(void) > { > - struct device_node *qe; > - int size; > - unsigned int num_of_snums; > - const u32 *prop; > - > - num_of_snums = 28; /* The default number of snum for threads is 28 > */ > - qe = qe_get_device_node(); > - if (!qe) > - return num_of_snums; > - > - prop = of_get_property(qe, "fsl,qe-num-snums", &size); > - if (prop && size == sizeof(*prop)) { > - num_of_snums = *prop; > - if ((num_of_snums < 28) || (num_of_snums > > QE_NUM_OF_SNUM)) { > - /* No QE ever has fewer than 28 SNUMs */ > - pr_err("QE: number of snum is invalid\n"); > - of_node_put(qe); > - return -EINVAL; > - } > - } > - > - of_node_put(qe); > - > - return num_of_snums; > + return qe_num_of_snum; > } > EXPORT_SYMBOL(qe_get_num_of_snums); > > -- > 2.20.1 Best Regards Qiang Zhao
diff --git a/drivers/soc/fsl/qe/qe.c b/drivers/soc/fsl/qe/qe.c index 325d689cbf5c..276d7d78ebfc 100644 --- a/drivers/soc/fsl/qe/qe.c +++ b/drivers/soc/fsl/qe/qe.c @@ -308,24 +308,33 @@ static void qe_snums_init(void) int i; bitmap_zero(snum_state, QE_NUM_OF_SNUM); + qe_num_of_snum = 28; /* The default number of snum for threads is 28 */ qe = qe_get_device_node(); if (qe) { i = of_property_read_variable_u8_array(qe, "fsl,qe-snums", snums, 1, QE_NUM_OF_SNUM); - of_node_put(qe); if (i > 0) { + of_node_put(qe); qe_num_of_snum = i; return; } + /* + * Fall back to legacy binding of using the value of + * fsl,qe-num-snums to choose one of the static arrays + * above. + */ + of_property_read_u32(qe, "fsl,qe-num-snums", &qe_num_of_snum); + of_node_put(qe); } - qe_num_of_snum = qe_get_num_of_snums(); - - if (qe_num_of_snum == 76) + if (qe_num_of_snum == 76) { snum_init = snum_init_76; - else + } else if (qe_num_of_snum == 28 || qe_num_of_snum == 46) { snum_init = snum_init_46; - + } else { + pr_err("QE: unsupported value of fsl,qe-num-snums: %u\n", qe_num_of_snum); + return; + } memcpy(snums, snum_init, qe_num_of_snum); } @@ -641,30 +650,7 @@ EXPORT_SYMBOL(qe_get_num_of_risc); unsigned int qe_get_num_of_snums(void) { - struct device_node *qe; - int size; - unsigned int num_of_snums; - const u32 *prop; - - num_of_snums = 28; /* The default number of snum for threads is 28 */ - qe = qe_get_device_node(); - if (!qe) - return num_of_snums; - - prop = of_get_property(qe, "fsl,qe-num-snums", &size); - if (prop && size == sizeof(*prop)) { - num_of_snums = *prop; - if ((num_of_snums < 28) || (num_of_snums > QE_NUM_OF_SNUM)) { - /* No QE ever has fewer than 28 SNUMs */ - pr_err("QE: number of snum is invalid\n"); - of_node_put(qe); - return -EINVAL; - } - } - - of_node_put(qe); - - return num_of_snums; + return qe_num_of_snum; } EXPORT_SYMBOL(qe_get_num_of_snums);
The comment "No QE ever has fewer than 28 SNUMs" is false; e.g. the MPC8309 has 14. The code path returning -EINVAL is also a recipe for instant disaster, since the caller (qe_snums_init) uncritically assigns the return value to the unsigned qe_num_of_snum, and would thus proceed to attempt to copy 4GB from snum_init_46[] to the snum[] array. So fold the handling of the legacy fsl,qe-num-snums into qe_snums_init, and make sure we do not end up using the snum_init_46 array in cases other than the two where we know it makes sense. Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> --- drivers/soc/fsl/qe/qe.c | 46 ++++++++++++++--------------------------- 1 file changed, 16 insertions(+), 30 deletions(-)