[Cocci] coccinelle and bitmask arithmetic (was: Re: [patch] TTY: synclink, small cleanup in dtr_rts())

[Cocci] coccinelle and bitmask arithmetic (was: Re: [patch] TTY: synclink, small cleanup in dtr_rts())

[Joe Perches]

On Tue, 2013-01-29 at 10:55 -0500, Valdis.Kletnieks at vt.edu wrote:
> On Sun, 27 Jan 2013 23:19:47 +0300, Dan Carpenter said:
> 
> > Yeah.  I think it would be, but adding bitflags together instead of
> > doing bitwise ORs is very common as well.
> 
> The fact it's common doesn't mean it's good programming practice,
> or even correct.  Consider:
> 
> #define F_FOO 0x01
> #define F_BAR 0x02
> #define F_BAZ 0x04
> 
> unsigned int flags = F_FOO;
> ...
>       flags |= F_BAR;
> 
> Now some time later, another code path does this:
> 
>       flags += F_FOO;
> 
> If it was another |, it would be a no harm no foul class of bug.
> But how long is it going to take you to figure out who set F_BAZ?
> 
> I wonder if there's a way to write a coccinelle patch to find places
> where we do arithmetic operations on bitmasks....

Not so far as I know, but maybe someone on the
cocci lists does. (cc'd)

I could imagine a test for variables that have
uses of both arithmetic and bit operations but
not a discriminator for when one type is
appropriate and the other is not.

[Cocci] coccinelle and bitmask arithmetic (was: Re: [patch] TTY: synclink, small cleanup in dtr_rts())

[Julia Lawall]

On Tue, 29 Jan 2013, Joe Perches wrote:

> On Tue, 2013-01-29 at 10:55 -0500, Valdis.Kletnieks at vt.edu wrote:
> > On Sun, 27 Jan 2013 23:19:47 +0300, Dan Carpenter said:
> >
> > > Yeah.  I think it would be, but adding bitflags together instead of
> > > doing bitwise ORs is very common as well.
> >
> > The fact it's common doesn't mean it's good programming practice,
> > or even correct.  Consider:
> >
> > #define F_FOO 0x01
> > #define F_BAR 0x02
> > #define F_BAZ 0x04
> >
> > unsigned int flags = F_FOO;
> > ...
> >       flags |= F_BAR;
> >
> > Now some time later, another code path does this:
> >
> >       flags += F_FOO;
> >
> > If it was another |, it would be a no harm no foul class of bug.
> > But how long is it going to take you to figure out who set F_BAZ?
> >
> > I wonder if there's a way to write a coccinelle patch to find places
> > where we do arithmetic operations on bitmasks....
>
> Not so far as I know, but maybe someone on the
> cocci lists does. (cc'd)
>
> I could imagine a test for variables that have
> uses of both arithmetic and bit operations but
> not a discriminator for when one type is
> appropriate and the other is not.

If the definition of a bitmask is an identifier in all capital letters,
that would be easy.  Another possibility is such an identifier that is
defined to a value expressed beginning with 0x.  Another possibility is
such an identifier that is sometimes used with & and | and sometimes used
with an arithmetic operation.  I will give them a try.

julia

[Cocci] coccinelle and bitmask arithmetic (was: Re: [patch] TTY: synclink, small cleanup in dtr_rts())

[Joe Perches]

On Tue, 2013-01-29 at 17:19 +0100, Julia Lawall wrote:
> > On Tue, 2013-01-29 at 10:55 -0500, Valdis.Kletnieks at vt.edu wrote:
[]
> > > I wonder if there's a way to write a coccinelle patch to find places
> > > where we do arithmetic operations on bitmasks....
[]
> If the definition of a bitmask is an identifier in all capital letters,
> that would be easy.  Another possibility is such an identifier that is
> defined to a value expressed beginning with 0x.  Another possibility is
> such an identifier that is sometimes used with & and | and sometimes used
> with an arithmetic operation.  I will give them a try.

Thanks Julia.

[Cocci] coccinelle and bitmask arithmetic (was: Re: [patch] TTY: synclink, small cleanup in dtr_rts())

[Dan Carpenter]

On Tue, Jan 29, 2013 at 05:19:43PM +0100, Julia Lawall wrote:
> If the definition of a bitmask is an identifier in all capital letters,
> that would be easy.  Another possibility is such an identifier that is
> defined to a value expressed beginning with 0x.  Another possibility is
> such an identifier that is sometimes used with & and | and sometimes used
> with an arithmetic operation.  I will give them a try.
> 

Oddly enough, this thread started because I wrote a script to do
this in Smatch.  It turns out not as useful as I had hoped, so I
wasn't planning to push it.

Anyway, I've gzipped it and attached it.  It's 350k because it has
a list of 50k macros which were used as bit masks.  Hopefully, it's
helpful.

It generates 350 warnings, but they are almost all false positives.
I have sent two patches based on the output.

regards,
dan carpenter

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[Cocci] coccinelle and bitmask arithmetic (was: Re: [patch] TTY: synclink, small cleanup in dtr_rts())

[Dan Carpenter]

Here are the warnings for yesterday's linux-next (next-20130128).

regards,
dan carpenter

arch/x86/crypto/crc32-pclmul_glue.c:66 crc32_pclmul_le() warn: bit mask 'SCALE_F_MASK' used for math 'p + (16 - 1)'
arch/x86/kernel/cpu/mcheck/mce_amd.c:155 threshold_restart_bank() warn: bit mask 'THRESHOLD_MAX' used for math '4095 - tr->b->threshold_limit'
arch/x86/kernel/cpu/mcheck/mce_amd.c:400 show_error_count() warn: bit mask 'THRESHOLD_MAX' used for math '4095 - b->threshold_limit'
arch/x86/realmode/init.c:81 setup_real_mode() warn: bit mask '_KERNPG_TABLE' used for math '__phys_addr_symbol(((level3_ident_pgt))) + ((((1)) << 0) | (((1)) << 1) | (((1)) << 5) | (((1)) << 6))'
arch/x86/realmode/init.c:82 setup_real_mode() warn: bit mask '_KERNPG_TABLE' used for math '__phys_addr_symbol(((level3_kernel_pgt))) + ((((1)) << 0) | (((1)) << 1) | (((1)) << 5) | (((1)) << 6))'
arch/x86/kvm/x86.c:1560 msr_mtrr_valid() warn: bit mask 'KVM_NR_VAR_MTRR' used for math '2 * 8'
fs/proc/mmu.c:55 get_vmalloc_info() warn: bit mask 'VMALLOC_END' used for math '(-25288767438849) - prev_end'
fs/proc/mmu.c:56 get_vmalloc_info() warn: bit mask 'VMALLOC_END' used for math '(-25288767438849) - prev_end'
fs/proc/kcore.c:225 kclist_add_private() warn: bit mask 'VMALLOC_START' used for math '(-60473139527680) - ent->addr'
fs/proc/kcore.c:226 kclist_add_private() warn: bit mask 'VMALLOC_START' used for math '(-60473139527680) - ent->addr'
fs/proc/kcore.c:629 proc_kcore_init() warn: bit mask 'VMALLOC_END' used for math '(-25288767438849) - (-60473139527680)'
fs/proc/kcore.c:629 proc_kcore_init() warn: bit mask 'VMALLOC_START' used for math '(-25288767438849) - (-60473139527680)'
fs/inode.c:460 hash() warn: bit mask 'GOLDEN_RATIO_PRIME' used for math '-7045881617021403135 + hashval'
fs/udf/inode.c:1009 udf_merge_extents() warn: bit mask 'UDF_EXTENT_LENGTH_MASK' used for math 'lip1->extLength - (li->extLength & 1073741823) + 1073741823'
fs/udf/inode.c:1014 udf_merge_extents() warn: bit mask 'UDF_EXTENT_LENGTH_MASK' used for math '1073741823 + 1'
fs/udf/inode.c:1049 udf_merge_extents() warn: bit mask 'UDF_EXTENT_LENGTH_MASK' used for math 'lip1->extLength - (li->extLength & 1073741823) + 1073741823'
fs/udf/inode.c:1054 udf_merge_extents() warn: bit mask 'UDF_EXTENT_LENGTH_MASK' used for math '1073741823 + 1'
fs/jffs2/compr_rubin.c:98 init_rubin() warn: bit mask 'UPPER_BIT_RUBIN' used for math '2 * ((1) << (16 - 1))'
fs/ubifs/lprops.c:189 add_to_lpt_heap() warn: bit mask 'b' used for math '((lprops >> 4) & b) + b'
fs/nfs/blocklayout/blocklayout.c:520 bl_do_readpage_sync() warn: bit mask 'SECTOR_SIZE' used for math 'offset / (1 << 9)'
net/batman-adv/translation-table.c:1615 batadv_tt_response_fill_table() warn: bit mask 'NET_IP_ALIGN' used for math 'len + 14 + 0'
net/batman-adv/translation-table.c:1782 batadv_send_other_tt_response() warn: bit mask 'NET_IP_ALIGN' used for math 'len + 14 + 0'
net/batman-adv/translation-table.c:1900 batadv_send_my_tt_response() warn: bit mask 'NET_IP_ALIGN' used for math 'len + 14 + 0'
net/batman-adv/vis.c:400 batadv_add_packet() warn: bit mask 'NET_IP_ALIGN' used for math 'len + 14 + 0'
net/batman-adv/icmp_socket.c:180 batadv_socket_write() warn: bit mask 'NET_IP_ALIGN' used for math 'packet_len + 14 + 0'
net/dsa/tag_trailer.c:37 trailer_xmit() warn: bit mask 'NET_IP_ALIGN' used for math '0 + skb->len'
net/sched/sch_prio.c:186 prio_tune() warn: bit mask 'TC_PRIO_MAX' used for math '15 + 1'
net/sched/sch_prio.c:248 prio_dump() warn: bit mask 'TC_PRIO_MAX' used for math '15 + 1'
net/sched/sch_sfb.c:392 sfb_enqueue() warn: bit mask 'SFB_MAX_PROB' used for math '65535 / 2'
net/sched/sch_generic.c:494 pfifo_fast_dump() warn: bit mask 'TC_PRIO_MAX' used for math '15 + 1'
net/ieee802154/6lowpan.c:259 lowpan_compress_udp_header() warn: bit mask 'LOWPAN_NHC_UDP_4BIT_PORT' used for math 'uh->dest - 61616'
net/ieee802154/6lowpan.c:344 lowpan_uncompress_udp_header() warn: bit mask 'LOWPAN_NHC_UDP_4BIT_PORT' used for math '61616 + (*skb->data + 0 >> 4)'
net/ieee802154/6lowpan.c:346 lowpan_uncompress_udp_header() warn: bit mask 'LOWPAN_NHC_UDP_4BIT_PORT' used for math '61616 + (*skb->data + 0 & 15)'
net/core/neighbour.c:1543 neigh_table_init_no_netlink() warn: bit mask 'PNEIGH_HASHMASK' used for math '15 + 1'
net/core/dev.c:3874 napi_reuse_skb() warn: bit mask 'NET_IP_ALIGN' used for math ' + 0'
net/openvswitch/datapath.c:669 ovs_packet_cmd_execute() warn: bit mask 'NET_IP_ALIGN' used for math '0 + len'
net/rds/iw_rdma.c:300 rds_iw_map_scatterlist() warn: bit mask 'PAGE_MASK' used for math 'end_addr + (~(((1) << 12) - 1))'
sound/pci/pcxhr/pcxhr_core.c:1249 pcxhr_interrupt() warn: bit mask 'PCXHR_DSP_TIME_MASK' used for math 'dsp_time_diff + 16777215'
sound/pci/intel8x0m.c:398 snd_intel8x0m_setup_periods() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/intel8x0m.c:398 snd_intel8x0m_setup_periods() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/intel8x0m.c:410 snd_intel8x0m_setup_periods() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/intel8x0m.c:410 snd_intel8x0m_setup_periods() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/intel8x0m.c:455 snd_intel8x0m_update() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/intel8x0.c:684 snd_intel8x0_setup_periods() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/intel8x0.c:684 snd_intel8x0_setup_periods() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/intel8x0.c:696 snd_intel8x0_setup_periods() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/intel8x0.c:696 snd_intel8x0_setup_periods() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/intel8x0.c:767 snd_intel8x0_update() warn: bit mask 'ICH_REG_LVI_MASK' used for math '31 + 1'
sound/pci/cs4281.c:1024 snd_cs4281_get_volume() warn: bit mask 'CS_VOL_MASK' used for math '31 - (snd_cs4281_peekBA0(regL, chip) & 31)'
sound/pci/cs4281.c:1025 snd_cs4281_get_volume() warn: bit mask 'CS_VOL_MASK' used for math '31 - (snd_cs4281_peekBA0(regR, chip) & 31)'
sound/pci/cs4281.c:1041 snd_cs4281_put_volume() warn: bit mask 'CS_VOL_MASK' used for math '31 - (snd_cs4281_peekBA0(regL, chip) & 31)'
sound/pci/cs4281.c:1042 snd_cs4281_put_volume() warn: bit mask 'CS_VOL_MASK' used for math '31 - (snd_cs4281_peekBA0(regR, chip) & 31)'
sound/pci/cs4281.c:1045 snd_cs4281_put_volume() warn: bit mask 'CS_VOL_MASK' used for math '31 - (ucontrol->value.integer.value[0] & 31)'
sound/pci/cs4281.c:1050 snd_cs4281_put_volume() warn: bit mask 'CS_VOL_MASK' used for math '31 - (ucontrol->value.integer.value[1] & 31)'
sound/drivers/opl3/opl3_midi.c:74 snd_opl3_calc_volume() warn: bit mask 'OPL3_TOTAL_LEVEL_MASK' used for math '63 - (*volbyte & 63)'
sound/drivers/opl3/opl3_midi.c:82 snd_opl3_calc_volume() warn: bit mask 'OPL3_TOTAL_LEVEL_MASK' used for math '63 - (newvol & 63)'
sound/firewire/isight.c:625 get_unit_base() warn: bit mask 'CSR_REGISTER_BASE' used for math '281474708275200 + value * 4'
sound/firewire/cmp.c:65 pcr_modify() warn: bit mask 'CSR_REGISTER_BASE' used for math '281474708275200 + (2436 + (c->pcr_index) * 4)'
mm/rmap.c:970 page_move_anon_rmap() warn: bit mask 'PAGE_MAPPING_ANON' used for math 'anon_vma + 1'
mm/rmap.c:999 __page_set_anon_rmap() warn: bit mask 'PAGE_MAPPING_ANON' used for math 'anon_vma + 1'
mm/rmap.c:1783 __hugepage_set_anon_rmap() warn: bit mask 'PAGE_MAPPING_ANON' used for math 'anon_vma + 1'
mm/vmalloc.c:1172 vm_area_register_early() warn: bit mask 'VMALLOC_START' used for math '(((addr + vm->size) + (((1) << 12) - 1)) & (~(((1) << 12) - 1))) - (-60473139527680)'
mm/percpu.c:1689 pcpu_embed_first_chunk() warn: bit mask 'VMALLOC_END' used for math '(-25288767438849) - (-60473139527680)'
mm/percpu.c:1689 pcpu_embed_first_chunk() warn: bit mask 'VMALLOC_START' used for math '(-25288767438849) - (-60473139527680)'
drivers/staging/fwserial/fwserial.c:2057 fwserial_add_peer() warn: bit mask 'CSR_REGISTER_BASE' used for math '281474708275200 + 4 * val'
drivers/staging/iio/light/tsl2x7x_core.c:774 tsl2x7x_chip_on() warn: bit mask 'TSL2X7X_CMD_REG' used for math '128 + i'
drivers/staging/iio/light/tsl2583.c:443 taos_chip_on() warn: bit mask 'TSL258X_CMD_REG' used for math '128 + i'
drivers/staging/iio/light/tsl2583.c:834 taos_probe() warn: bit mask 'TSL258X_CNTRL' used for math '0 + i'
drivers/staging/media/lirc/lirc_igorplugusb.c:333 igorplugusb_remote_poll() warn: bit mask 'PULSE_MASK' used for math '16777215 / 1000000'
drivers/staging/media/go7007/wis-saa7113.c:144 wis_saa7113_command() warn: bit mask 'V4L2_STD_SECAM' used for math 'dec->norm * ((65536) | (262144) | (524288) | ((131072) | (1048576) | (2097152)) | (4194304) | (8388608))'
drivers/iommu/amd_iommu.c:3552 amd_iommu_domain_enable_v2() warn: bit mask 'PASID_MASK' used for math '1048575 + 1'
drivers/iommu/amd_iommu_v2.c:763 amd_iommu_init_device() warn: bit mask 'PASID_MASK' used for math '1048575 + 1'
drivers/usb/c67x00/c67x00-sched.c:202 frame_after() warn: bit mask 'HOST_FRAME_MASK' used for math '2047 + a'
drivers/usb/c67x00/c67x00-sched.c:203 frame_after() warn: bit mask 'HOST_FRAME_MASK' used for math '2047 / 2'
drivers/usb/c67x00/c67x00-sched.c:211 frame_after_eq() warn: bit mask 'HOST_FRAME_MASK' used for math '2047 + 1'
drivers/usb/c67x00/c67x00-sched.c:212 frame_after_eq() warn: bit mask 'HOST_FRAME_MASK' used for math '2047 / 2'
drivers/usb/core/message.c:1188 usb_disable_device() warn: bit mask 'USB_DIR_IN' used for math 'i + 128'
drivers/usb/core/message.c:1198 usb_disable_device() warn: bit mask 'USB_DIR_IN' used for math 'i + 128'
drivers/usb/core/message.c:1447 usb_reset_configuration() warn: bit mask 'USB_DIR_IN' used for math 'i + 128'
drivers/usb/host/xhci-mem.c:2410 xhci_mem_init() warn: bit mask 'ERST_NUM_SEGS' used for math '16 * 1'
drivers/usb/host/uhci-hcd.c:598 uhci_start() warn: bit mask 'UHCI_NUMFRAMES' used for math '1024 * '
drivers/usb/misc/sisusbvga/sisusb.c:2537 sisusb_read() warn: bit mask 'SISUSB_PCI_IOPORTBASE' used for math '(*ppos) - 53248 + 53248'
drivers/usb/misc/sisusbvga/sisusb.c:2592 sisusb_read() warn: bit mask 'SISUSB_PCI_MEMBASE' used for math '(*ppos) - 268435456 + 3489660928'
drivers/usb/misc/sisusbvga/sisusb.c:2608 sisusb_read() warn: bit mask 'SISUSB_PCI_MMIOBASE' used for math '(*ppos) - 536870912 + 3825205248'
drivers/usb/misc/sisusbvga/sisusb.c:2679 sisusb_write() warn: bit mask 'SISUSB_PCI_IOPORTBASE' used for math '(*ppos) - 53248 + 53248'
drivers/usb/misc/sisusbvga/sisusb.c:2733 sisusb_write() warn: bit mask 'SISUSB_PCI_MEMBASE' used for math '(*ppos) - 268435456 + 3489660928'
drivers/usb/misc/sisusbvga/sisusb.c:2752 sisusb_write() warn: bit mask 'SISUSB_PCI_MMIOBASE' used for math '(*ppos) - 536870912 + 3825205248'
drivers/usb/misc/sisusbvga/sisusb.c:2852 sisusb_handle_command() warn: bit mask 'SISUSB_PCI_IOPORTBASE' used for math 'y->data3 - 53248 + 53248'
drivers/usb/misc/sisusbvga/sisusb.c:2898 sisusb_handle_command() warn: bit mask 'SISUSB_PCI_MEMBASE' used for math 'y->data3 - 268435456 + 3489660928'
drivers/usb/misc/sisusbvga/sisusb_con.c:679 sisusbcon_blank() warn: bit mask 'VESA_VSYNC_SUSPEND' used for math '1 + 1'
drivers/usb/atm/usbatm.c:342 usbatm_extract_one_cell() warn: bit mask 'ATM_CELL_PAYLOAD' used for math 'sarb->tail + 48'
drivers/usb/atm/usbatm.c:489 usbatm_write_cells() warn: bit mask 'ATM_CELL_PAYLOAD' used for math '48 - data_len'
drivers/net/tun.c:1070 tun_get_user() warn: bit mask 'NET_IP_ALIGN' used for math ''
drivers/net/xen-netback/netback.c:1336 xen_netbk_tx_build_gops() warn: bit mask 'NET_IP_ALIGN' used for math 'data_len +  + 0'
drivers/net/xen-netback/netback.c:1346 xen_netbk_tx_build_gops() warn: bit mask 'NET_IP_ALIGN' used for math ' + 0'
drivers/net/usb/smsc95xx.c:1741 smsc95xx_rx_fixup() warn: bit mask 'NET_IP_ALIGN' used for math 'size + 0'
drivers/net/ethernet/marvell/skge.c:1011 skge_rx_fill() warn: bit mask 'NET_IP_ALIGN' used for math 'skge->rx_buf_size + 0'
drivers/net/ethernet/intel/ixgbe/ixgbe_common.c:1128 ixgbe_read_eerd_buffer_generic() warn: bit mask 'IXGBE_EEPROM_RW_REG_START' used for math '((offset + i) << 2) + 1'
drivers/net/ethernet/intel/ixgb/ixgb_main.c:1997 ixgb_check_copybreak() warn: bit mask 'NET_IP_ALIGN' used for math '(*skb)->data - 0'
drivers/net/ethernet/intel/ixgb/ixgb_main.c:1998 ixgb_check_copybreak() warn: bit mask 'NET_IP_ALIGN' used for math 'length + 0'
drivers/net/ethernet/intel/e1000/e1000_main.c:4234 e1000_check_copybreak() warn: bit mask 'NET_IP_ALIGN' used for math '(*skb)->data - 0'
drivers/net/ethernet/intel/e1000/e1000_main.c:4235 e1000_check_copybreak() warn: bit mask 'NET_IP_ALIGN' used for math 'length + 0'
drivers/net/ethernet/intel/e1000e/netdev.c:1013 e1000_clean_rx_irq() warn: bit mask 'NET_IP_ALIGN' used for math 'skb->data - 0'
drivers/net/ethernet/intel/e1000e/netdev.c:1015 e1000_clean_rx_irq() warn: bit mask 'NET_IP_ALIGN' used for math 'length + 0'
drivers/net/ethernet/intel/e1000e/nvm.c:333 e1000e_read_nvm_eerd() warn: bit mask 'E1000_NVM_RW_REG_START' used for math '((offset + i) << 2) + 1'
drivers/net/ethernet/intel/igb/e1000_nvm.c:410 igb_read_nvm_eerd() warn: bit mask 'E1000_NVM_RW_REG_START' used for math '((offset + i) << 2) + 1'
drivers/net/ethernet/dec/tulip/winbond-840.c:1019 start_tx() warn: bit mask 'TX_BUFLIMIT' used for math 'skb->len - (1024 - 128)'
drivers/net/ethernet/dec/tulip/winbond-840.c:1021 start_tx() warn: bit mask 'TX_BUFLIMIT' used for math 'np->tx_addr[entry] + (1024 - 128)'
drivers/net/ethernet/dec/tulip/de4x5.c:3394 test_for_100Mb() warn: bit mask 'SAMPLE_INTERVAL' used for math 'msec / 500'
drivers/net/ethernet/dec/tulip/de4x5.c:3396 test_for_100Mb() warn: bit mask 'SAMPLE_INTERVAL' used for math '(msec - 2000) / 500'
drivers/net/ethernet/dec/tulip/de4x5.c:3396 test_for_100Mb() warn: bit mask 'SAMPLE_DELAY' used for math 'msec - 2000'
drivers/net/ethernet/dec/tulip/de4x5.c:3400 test_for_100Mb() warn: bit mask 'SAMPLE_INTERVAL' used for math 'msec / 500'
drivers/net/ethernet/dec/tulip/de2104x.c:817 de_rx_missed() warn: bit mask 'RxMissedMask' used for math ''
drivers/net/ethernet/microchip/enc28j60.c:957 enc28j60_hw_rx() warn: bit mask 'NET_IP_ALIGN' used for math 'len + 0'
drivers/net/ethernet/neterion/s2io.c:2521 fill_rx_buffers() warn: bit mask 'NET_IP_ALIGN' used for math ''
drivers/net/ethernet/neterion/s2io.c:2547 fill_rx_buffers() warn: bit mask 'NET_IP_ALIGN' used for math 'size - 0'
drivers/net/ethernet/neterion/s2io.c:6836 set_rxd_buffer_pointer() warn: bit mask 'NET_IP_ALIGN' used for math 'size - 0'
drivers/net/ethernet/neterion/s2io.c:6933 rxd_owner_bit_reset() warn: bit mask 'NET_IP_ALIGN' used for math ''
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:568 init_dma_desc_rings() warn: bit mask 'NET_IP_ALIGN' used for math 'bfsize + 0'
drivers/net/ethernet/tehuti/tehuti.c:1104 bdx_rx_alloc_skbs() warn: bit mask 'NET_IP_ALIGN' used for math 'f->m.pktsz + 0'
drivers/net/ethernet/tehuti/tehuti.c:1274 bdx_rx_receive() warn: bit mask 'NET_IP_ALIGN' used for math 'len + 0'
drivers/net/ethernet/atheros/atlx/atl1.c:1670 atl1_via_workaround() warn: bit mask 'PCI_COMMAND' used for math 'adapter->hw.hw_addr + 4'
drivers/net/ethernet/atheros/atlx/atl1.c:1673 atl1_via_workaround() warn: bit mask 'PCI_COMMAND' used for math 'adapter->hw.hw_addr + 4'
drivers/net/ethernet/sfc/tx.c:104 efx_tx_queue_partner() warn: bit mask 'EFX_TXQ_TYPE_OFFLOAD' used for math 'tx_queue + 1'
drivers/net/ethernet/sfc/rx.c:155 efx_init_rx_buffers_skb() warn: bit mask 'NET_IP_ALIGN' used for math 'skb_len - 0'
drivers/net/ethernet/qlogic/qlge/qlge_main.c:1606 ql_process_mac_rx_skb() warn: bit mask 'NET_IP_ALIGN' used for math 'length + 0'
drivers/net/ethernet/qlogic/qlge/qlge_main.c:1694 ql_realign_skb() warn: bit mask 'NET_IP_ALIGN' used for math '0 - 0'
drivers/net/ethernet/qlogic/qlge/qlge_main.c:1695 ql_realign_skb() warn: bit mask 'NET_IP_ALIGN' used for math '0 - 0'
drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c:255 netxen_alloc_sw_resources() warn: bit mask 'NET_IP_ALIGN' used for math 'rds_ring->dma_size + 0'
drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c:272 netxen_alloc_sw_resources() warn: bit mask 'NET_IP_ALIGN' used for math 'rds_ring->dma_size + 0'
drivers/net/ethernet/qlogic/netxen/netxen_nic_init.c:278 netxen_alloc_sw_resources() warn: bit mask 'NET_IP_ALIGN' used for math 'rds_ring->dma_size + 0'
drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c:2617 qlcnic_83xx_get_registers() warn: bit mask 'QLCNIC_DEV_INFO_SIZE' used for math '1 + 1'
drivers/net/ethernet/qlogic/qlcnic/qlcnic_init.c:207 qlcnic_alloc_sw_resources() warn: bit mask 'NET_IP_ALIGN' used for math 'rds_ring->dma_size + 0'
drivers/net/ethernet/qlogic/qlcnic/qlcnic_init.c:220 qlcnic_alloc_sw_resources() warn: bit mask 'NET_IP_ALIGN' used for math 'rds_ring->dma_size + 0'
drivers/net/ethernet/qlogic/qlcnic/qlcnic_ethtool.c:216 qlcnic_get_regs_len() warn: bit mask 'QLCNIC_DEV_INFO_SIZE' used for math '(20 * 4) + len + 1'
drivers/net/ethernet/qlogic/qlcnic/qlcnic_ethtool.c:460 qlcnic_82xx_get_registers() warn: bit mask 'QLCNIC_DEV_INFO_SIZE' used for math '1 + 1'
drivers/net/ethernet/cadence/macb.c:553 macb_rx_frame() warn: bit mask 'NET_IP_ALIGN' used for math 'len + 0'
drivers/net/ethernet/cadence/macb.c:570 macb_rx_frame() warn: bit mask 'NET_IP_ALIGN' used for math ''
drivers/net/ethernet/mellanox/mlx4/reset.c:174 mlx4_reset() warn: bit mask 'PCI_COMMAND' used for math '4 / 4'
drivers/net/ethernet/amd/pcnet32.c:1175 pcnet32_rx_entry() warn: bit mask 'NET_IP_ALIGN' used for math 'pkt_len + 0'
drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c:1409 pch_gbe_alloc_rx_buffers() warn: bit mask 'NET_IP_ALIGN' used for math 'adapter->rx_buffer_len + 0'
drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c:1503 pch_gbe_alloc_tx_buffers() warn: bit mask 'NET_IP_ALIGN' used for math 'adapter->hw.mac.max_frame_size + 0 + 0'
drivers/net/ethernet/rdc/r6040.c:219 r6040_phy_read() warn: bit mask 'MDIO_READ' used for math '8192 + reg'
drivers/net/ethernet/rdc/r6040.c:239 r6040_phy_write() warn: bit mask 'MDIO_WRITE' used for math '16384 + reg'
drivers/net/ethernet/micrel/ksz884x.c:1817 port_r_mib_cnt() warn: bit mask 'MIB_COUNTER_VALUE' used for math '1073741823 + 1'
drivers/net/ethernet/micrel/ksz884x.c:1861 port_r_mib_pkt() warn: bit mask 'MIB_PACKET_DROPPED' used for math '65535 + 1'
drivers/net/ethernet/broadcom/b44.c:657 b44_alloc_rx_skb() warn: bit mask 'RX_PKT_BUF_SZ' used for math 'mapping + (1536 + (28 + 2))'
drivers/net/ethernet/broadcom/b44.c:670 b44_alloc_rx_skb() warn: bit mask 'RX_PKT_BUF_SZ' used for math 'mapping + (1536 + (28 + 2))'
drivers/net/ethernet/broadcom/b44.c:774 b44_rx() warn: bit mask 'RX_PKT_BUF_SZ' used for math '(1536 + (28 + 2)) - (28 + 2)'
drivers/net/ethernet/broadcom/tg3.c:15749 tg3_get_invariants() warn: bit mask 'NET_IP_ALIGN' used for math ' + 0'
drivers/net/ethernet/broadcom/cnic.c:5001 cnic_init_bnx2x_rx_ring() warn: bit mask 'BNX2X_MAX_RCQ_DESC_CNT' used for math ''
drivers/net/ethernet/smsc/smsc9420.c:829 smsc9420_rx_handoff() warn: bit mask 'NET_IP_ALIGN' used for math 'skb_tail_pointer(skb) + 0'
drivers/net/ethernet/smsc/smsc9420.c:866 smsc9420_alloc_rx_buffer() warn: bit mask 'NET_IP_ALIGN' used for math 'mapping + 0'
drivers/net/wimax/i2400m/rx.c:932 i2400m_rx_roq_destroy() warn: bit mask 'I2400M_RO_CIN' used for math '15 + 1'
drivers/net/wimax/i2400m/rx.c:932 i2400m_rx_roq_destroy() warn: bit mask 'I2400M_RO_CIN' used for math '15 + 1'
drivers/net/wimax/i2400m/rx.c:1359 i2400m_rx_setup() warn: bit mask 'I2400M_RO_CIN' used for math '15 + 1'
drivers/net/wimax/i2400m/rx.c:1367 i2400m_rx_setup() warn: bit mask 'I2400M_RO_CIN' used for math '15 + 1'
drivers/net/wimax/i2400m/rx.c:1376 i2400m_rx_setup() warn: bit mask 'I2400M_RO_CIN' used for math '15 + 1'
drivers/net/wimax/i2400m/rx.c:1376 i2400m_rx_setup() warn: bit mask 'I2400M_RO_CIN' used for math '15 + 1'
drivers/net/wireless/ray_cs.c:2377 copy_from_rx_buff() warn: bit mask 'RX_BUFF_END' used for math '16383 + 1'
drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c:3740 brcmf_sdbrcm_probe_attach() warn: bit mask 'PRIOMASK' used for math '7 + 1'
drivers/net/wireless/ath/carl9170/rx.c:471 carl9170_rx_copy_data() warn: bit mask 'NET_IP_ALIGN' used for math ''
drivers/net/wireless/ath/carl9170/rx.c:474 carl9170_rx_copy_data() warn: bit mask 'NET_IP_ALIGN' used for math ''
drivers/net/wireless/ath/carl9170/rx.c:478 carl9170_rx_copy_data() warn: bit mask 'NET_IP_ALIGN' used for math ''
drivers/net/wireless/ath/ath6kl/txrx.c:1152 aggr_process_recv_frm() warn: bit mask 'ATH6KL_MAX_SEQ_NO' used for math '4095 - (rxtid->hold_q_sz - 2 - cur)'
drivers/net/wireless/ath/ath6kl/txrx.c:1163 aggr_process_recv_frm() warn: bit mask 'ATH6KL_MAX_SEQ_NO' used for math '4095 - (rxtid->hold_q_sz - 2 - cur)'
drivers/net/wireless/ti/wl1251/tx.c:40 wl1251_tx_double_buffer_busy() warn: bit mask 'TX_STATUS_DATA_OUT_COUNT_MASK' used for math '15 + 1'
drivers/md/persistent-data/dm-space-map-common.c:133 bitmap_word_used() warn: bit mask 'WORD_MASK_HIGH' used for math 'bits + -6148914691236517206'
drivers/md/dm-bufio.c:1654 dm_bufio_init() warn: bit mask 'VMALLOC_END' used for math '(-25288767438849) - (-60473139527680)'
drivers/md/dm-bufio.c:1654 dm_bufio_init() warn: bit mask 'VMALLOC_START' used for math '(-25288767438849) - (-60473139527680)'
drivers/md/dm-bufio.c:1655 dm_bufio_init() warn: bit mask 'VMALLOC_END' used for math '(-25288767438849) - (-60473139527680)'
drivers/md/dm-bufio.c:1655 dm_bufio_init() warn: bit mask 'VMALLOC_START' used for math '(-25288767438849) - (-60473139527680)'
drivers/rtc/rtc-ds1305.c:550 ds1305_nvram_read() warn: bit mask 'DS1305_NVRAM' used for math '32 + off'
drivers/rtc/rtc-msm6242.c:172 msm6242_set_time() warn: bit mask 'MSM6242_HOUR10_PM' used for math '(1 << 2) + (tm->tm_hour - 12) / 10'
drivers/gpu/drm/gma500/psb_intel_lvds.c:118 psb_lvds_i2c_set_brightness() warn: bit mask 'BRIGHTNESS_MASK' used for math 'level * 255'
drivers/gpu/drm/gma500/psb_intel_lvds.c:123 psb_lvds_i2c_set_brightness() warn: bit mask 'BRIGHTNESS_MASK' used for math '255 - blc_i2c_brightness'
drivers/ide/ide-eh.c:39 ide_ata_error() warn: bit mask 'SECTOR_SIZE' used for math 'nsect * 512'
drivers/ide/ide-disk_proc.c:102 __idedisk_proc_show() warn: bit mask 'SECTOR_SIZE' used for math '512 / 2'
drivers/ide/ide-disk_proc.c:102 __idedisk_proc_show() warn: bit mask 'SECTOR_SIZE' used for math '512 / 2'
drivers/ide/ide-taskfile.c:317 ide_error_cmd() warn: bit mask 'SECTOR_SIZE' used for math ''
drivers/ide/ide-taskfile.c:445 ide_raw_taskfile() warn: bit mask 'SECTOR_SIZE' used for math 'nsect * 512'
drivers/ide/ide-taskfile.c:596 ide_taskfile_ioctl() warn: bit mask 'SECTOR_SIZE' used for math 'taskout / 512'
drivers/ide/ide-taskfile.c:614 ide_taskfile_ioctl() warn: bit mask 'SECTOR_SIZE' used for math 'taskin / 512'
drivers/ide/ide-ioctls.c:158 ide_cmd_ioctl() warn: bit mask 'SECTOR_SIZE' used for math '512 * args[3]'
drivers/ide/tc86c001.c:125 tc86c001_dma_start() warn: bit mask 'SECTOR_SIZE' used for math '512 / 2'
drivers/ide/ide-proc.c:134 ide_identify_proc_show() warn: bit mask 'SECTOR_SIZE' used for math '512 / 2'
drivers/ide/ide-proc.c:134 ide_identify_proc_show() warn: bit mask 'SECTOR_SIZE' used for math '512 / 2'
drivers/input/joydev.c:808 joydev_connect() warn: bit mask 'KEY_MAX' used for math '767 - 256'
drivers/input/joydev.c:808 joydev_connect() warn: bit mask 'KEY_MAX' used for math '767 - 256'
drivers/media/pci/mantis/mantis_ioc.c:104 mantis_stream_control() warn: bit mask 'MANTIS_BYPASS' used for math '255 - (1 << 2)'
drivers/media/pci/mantis/mantis_ioc.c:114 mantis_stream_control() warn: bit mask 'MANTIS_BYPASS' used for math '255 - (1 << 2)'
drivers/media/pci/cx23885/cx23888-ir.c:338 pulse_clocks_to_clock_divider() warn: bit mask 'RXCLK_RCD' used for math '65535 + 1'
drivers/media/pci/cx23885/cx23888-ir.c:186 count_to_clock_divider() warn: bit mask 'RXCLK_RCD' used for math '65535 + 1'
drivers/media/usb/gspca/ov519.c:4064 sethvflip() warn: bit mask 'OV7670_MVFP_MIRROR' used for math '32 * hflip'
drivers/media/usb/gspca/ov519.c:4064 sethvflip() warn: bit mask 'OV7670_MVFP_VFLIP' used for math '16 * vflip'
drivers/media/usb/dvb-usb/af9005.c:616 af9005_boot_packet() warn: bit mask 'FW_BULKOUT_SIZE' used for math '250 + 2'
drivers/media/usb/dvb-usb/af9005.c:621 af9005_boot_packet() warn: bit mask 'FW_BULKOUT_SIZE' used for math '250 + 2'
drivers/media/usb/dvb-usb/af9005.c:733 af9005_download_firmware() warn: bit mask 'FW_BULKOUT_SIZE' used for math 'fw->size / 250'
drivers/media/usb/dvb-usb/af9005.c:737 af9005_download_firmware() warn: bit mask 'FW_BULKOUT_SIZE' used for math 'i * 250'
drivers/media/usb/dvb-usb/af9005.c:743 af9005_download_firmware() warn: bit mask 'FW_BULKOUT_SIZE' used for math '250 + 2'
drivers/media/dvb-frontends/dib0090.c:2471 dib0090_tune() warn: bit mask 'EN_CRYSTAL' used for math 'state->config->use_pwm_agc * 2'
drivers/media/i2c/cx25840/cx25840-ir.c:322 pulse_clocks_to_clock_divider() warn: bit mask 'RXCLK_RCD' used for math '65535 + 1'
drivers/media/i2c/cx25840/cx25840-ir.c:144 count_to_clock_divider() warn: bit mask 'RXCLK_RCD' used for math '65535 + 1'
drivers/ata/sata_mv.c:3678 mv_port_init() warn: bit mask 'ATA_REG_DATA' used for math '4 * 0'
drivers/ata/sata_mv.c:3681 mv_port_init() warn: bit mask 'ATA_REG_NSECT' used for math '4 * 2'
drivers/ata/sata_mv.c:3682 mv_port_init() warn: bit mask 'ATA_REG_LBAL' used for math '4 * 3'
drivers/ata/sata_mv.c:3685 mv_port_init() warn: bit mask 'ATA_REG_DEVICE' used for math '4 * 6'
drivers/ata/sata_nv.c:1296 nv_adma_setup_port() warn: bit mask 'ATA_REG_NSECT' used for math '2 * 4'
drivers/ata/sata_nv.c:1297 nv_adma_setup_port() warn: bit mask 'ATA_REG_LBAL' used for math '3 * 4'
drivers/ata/sata_nv.c:1300 nv_adma_setup_port() warn: bit mask 'ATA_REG_DEVICE' used for math '6 * 4'
drivers/ata/libata-sff.c:2245 ata_sff_std_ports() warn: bit mask 'ATA_REG_DATA' used for math 'ioaddr->cmd_addr + 0'
drivers/ata/libata-sff.c:2247 ata_sff_std_ports() warn: bit mask 'ATA_REG_FEATURE' used for math 'ioaddr->cmd_addr + 1'
drivers/ata/libata-sff.c:2248 ata_sff_std_ports() warn: bit mask 'ATA_REG_NSECT' used for math 'ioaddr->cmd_addr + 2'
drivers/ata/libata-sff.c:2249 ata_sff_std_ports() warn: bit mask 'ATA_REG_LBAL' used for math 'ioaddr->cmd_addr + 3'
drivers/ata/libata-sff.c:2252 ata_sff_std_ports() warn: bit mask 'ATA_REG_DEVICE' used for math 'ioaddr->cmd_addr + 6'
drivers/ata/libata-sff.c:2254 ata_sff_std_ports() warn: bit mask 'ATA_REG_CMD' used for math 'ioaddr->cmd_addr + 7'
drivers/mtd/rfd_ftl.c:139 build_block_map() warn: bit mask 'SECTOR_SIZE' used for math '(i + part->header_sectors_per_block) * 512'
drivers/mtd/rfd_ftl.c:157 scan_header() warn: bit mask 'SECTOR_SIZE' used for math 'part->block_size / 512'
drivers/mtd/rfd_ftl.c:166 scan_header() warn: bit mask 'SECTOR_SIZE' used for math '((3 + sectors_per_block) * 2 + 512 - 1) / 512'
drivers/mtd/rfd_ftl.c:166 scan_header() warn: bit mask 'SECTOR_SIZE' used for math '(3 + sectors_per_block) * 2 + 512'
drivers/mtd/rfd_ftl.c:404 move_block_contents() warn: bit mask 'SECTOR_SIZE' used for math '(i + part->header_sectors_per_block) * 512'
drivers/mtd/rfd_ftl.c:591 mark_sector_deleted() warn: bit mask 'SECTOR_SIZE' used for math '(old_addr % part->block_size) / 512'
drivers/mtd/rfd_ftl.c:667 do_writesect() warn: bit mask 'SECTOR_SIZE' used for math '(i + part->header_sectors_per_block) * 512'
drivers/mtd/ftl.c:434 prepare_xfer() warn: bit mask 'SECTOR_SIZE' used for math '(part->BlocksPerUnit * 4 + () + 512 - 1) / 512'
drivers/mtd/ftl.c:434 prepare_xfer() warn: bit mask 'SECTOR_SIZE' used for math 'part->BlocksPerUnit * 4 + () + 512'
drivers/mtd/ftl.c:548 copy_erase_unit() warn: bit mask 'SECTOR_SIZE' used for math ''
drivers/mtd/ftl.c:549 copy_erase_unit() warn: bit mask 'SECTOR_SIZE' used for math ''
drivers/mtd/ftl.c:805 ftl_read() warn: bit mask 'SECTOR_SIZE' used for math '(sector + i) * 512'
drivers/mtd/ftl.c:823 ftl_read() warn: bit mask 'SECTOR_SIZE' used for math ''
drivers/mtd/ftl.c:849 set_bam_entry() warn: bit mask 'SECTOR_SIZE' used for math '(log_addr % bsize) / 512'
drivers/mtd/ftl.c:925 ftl_write() warn: bit mask 'SECTOR_SIZE' used for math 'sector * 512'
drivers/mtd/ftl.c:943 ftl_write() warn: bit mask 'SECTOR_SIZE' used for math 'blk * 512'
drivers/mtd/ftl.c:950 ftl_write() warn: bit mask 'SECTOR_SIZE' used for math 'blk * 512'
drivers/mtd/ftl.c:976 ftl_write() warn: bit mask 'SECTOR_SIZE' used for math ''
drivers/mtd/ftl.c:977 ftl_write() warn: bit mask 'SECTOR_SIZE' used for math ''
drivers/mtd/ftl.c:988 ftl_getgeo() warn: bit mask 'SECTOR_SIZE' used for math '() / 512'
drivers/mtd/devices/docecc.c:199 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:199 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:210 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:210 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:213 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:218 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:218 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:213 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:225 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:225 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:281 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:281 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:290 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:306 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:306 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:318 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:319 eras_dec_rs() warn: bit mask 'NN' used for math 'Index_of[lambda[i]] - discr_r + ((1 << 10) - 1)'
drivers/mtd/devices/docecc.c:318 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:290 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:331 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:331 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:342 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) + k'
drivers/mtd/devices/docecc.c:374 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:374 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:385 eras_dec_rs() warn: bit mask 'NN' used for math '((1 << 10) - 1) - (1023 - 4)'
drivers/mtd/devices/docecc.c:397 eras_dec_rs() warn: bit mask 'NN' used for math 'root[j] * (510 - 1) + ((1 << 10) - 1)'
drivers/mtd/devices/docecc.c:415 eras_dec_rs() warn: bit mask 'NN' used for math 'Index_of[num1] + Index_of[num2] + ((1 << 10) - 1)'
drivers/mtd/devices/docecc.c:73 modnn() warn: bit mask 'NN' used for math ''
drivers/mtd/devices/docecc.c:448 doc_decode_ecc() warn: bit mask 'NN' used for math '((1 << 10) - 1) + 1'
drivers/mtd/devices/docecc.c:452 doc_decode_ecc() warn: bit mask 'NN' used for math '((1 << 10) - 1) + 1'
drivers/mtd/nand/docg4.c:526 read_progstatus() warn: bit mask 'DOC_IOSPACE_DATA' used for math 'docptr + 2048'
drivers/mtd/nand/docg4.c:527 read_progstatus() warn: bit mask 'DOC_IOSPACE_DATA' used for math 'docptr + 2048'
drivers/mtd/nand/docg4.c:781 read_page() warn: bit mask 'DOC_IOSPACE_DATA' used for math 'docptr + 2048'
drivers/mtd/nand/docg4.c:858 docg4_read_oob() warn: bit mask 'DOC_IOSPACE_DATA' used for math 'docptr + 2048'
drivers/mtd/nand/docg4.c:1235 init_mtd_structs() warn: bit mask 'DOC_IOSPACE_DATA' used for math 'doc->virtadr + 2048'
drivers/mtd/nand/diskonchip.c:174 doc_ecc_decode() warn: bit mask 'NN' used for math '1023 - 510'
drivers/xen/evtchn.c:175 evtchn_read() warn: bit mask 'EVTCHN_RING_SIZE' used for math '(((1) << 12) / 4) - ((c) & ((((1) << 12) / 4) - 1))'
drivers/video/aty/atyfb_base.c:1117 aty_var_to_crtc() warn: bit mask 'VERT_STRETCH_RATIO0' used for math '1023 + 1'
drivers/leds/leds-ss4200.c:283 ich7_gpio_init() warn: bit mask 'NAS_RECOVERY' used for math 'all_nas_led + 1024'
drivers/infiniband/ulp/iser/iser_verbs.c:195 iser_create_ib_conn_res() warn: bit mask 'ISCSI_DEF_MAX_RECV_SEG_LEN' used for math '8192 + ((32 + 48) + 8192)'
drivers/infiniband/ulp/iser/iser_verbs.c:201 iser_create_ib_conn_res() warn: bit mask 'ISCSI_DEF_MAX_RECV_SEG_LEN' used for math 'ib_conn->login_buf + 8192'
drivers/infiniband/hw/amso1100/c2.c:101 c2_set_rxbufsize() warn: bit mask 'NET_IP_ALIGN' used for math 'netdev->mtu + 14 + 8 + 0'
drivers/infiniband/hw/mthca/mthca_reset.c:224 mthca_reset() warn: bit mask 'PCI_COMMAND' used for math '4 / 4'
drivers/infiniband/hw/mthca/mthca_reset.c:274 mthca_reset() warn: bit mask 'PCI_COMMAND' used for math '4 / 4'
drivers/infiniband/hw/qib/qib_qsfp.c:474 qib_qsfp_init() warn: bit mask 'QSFP_GPIO_MOD_RST_N' used for math 'mask - (32)'
drivers/infiniband/hw/nes/nes_utils.c:399 nes_read16_eeprom() warn: bit mask 'NES_EEPROM_READ_REQUEST' used for math '(1 << 16) + (offset >> 1)'
drivers/isdn/hisax/hfc4s8s_l1.c:693 rx_d_frame() warn: bit mask 'MAX_F_CNT' used for math 'f1 - f2 + 15'
drivers/isdn/hisax/hfc_pci.c:361 receive_dmsg() warn: bit mask 'MAX_D_FRAMES' used for math '15 + 1'
drivers/isdn/hisax/hfc_pci.c:382 receive_dmsg() warn: bit mask 'MAX_D_FRAMES' used for math '15 + 1'
drivers/isdn/hisax/hfc_pci.c:495 main_rec_hfcpci() warn: bit mask 'MAX_B_FRAMES' used for math '31 + 1'
drivers/isdn/hisax/hfc_pci.c:538 hfcpci_fill_dfifo() warn: bit mask 'MAX_D_FRAMES' used for math '15 + 1'
drivers/isdn/hisax/hfc_pci.c:562 hfcpci_fill_dfifo() warn: bit mask 'D_FREG_MASK' used for math '15 + 1'
drivers/isdn/hisax/hfc_pci.c:672 hfcpci_fill_fifo() warn: bit mask 'MAX_B_FRAMES' used for math '31 + 1'
drivers/isdn/hisax/hfc_pci.c:912 receive_emsg() warn: bit mask 'MAX_B_FRAMES' used for math '31 + 1'
drivers/isdn/hisax/hfc_sx.c:158 write_fifo() warn: bit mask 'MAX_B_FRAMES' used for math '31 + 1'
drivers/isdn/hardware/mISDN/netjet.c:271 mode_tiger() warn: bit mask 'NJ_DMA_READ_ADR' used for math 'card->base + 20'
drivers/isdn/hardware/mISDN/netjet.c:272 mode_tiger() warn: bit mask 'NJ_DMA_WRITE_ADR' used for math 'card->base + 36'
drivers/isdn/hardware/mISDN/hfcpci.c:501 receive_dmsg() warn: bit mask 'MAX_D_FRAMES' used for math '15 + 1'
drivers/isdn/hardware/mISDN/hfcpci.c:533 receive_dmsg() warn: bit mask 'MAX_D_FRAMES' used for math '15 + 1'
drivers/isdn/hardware/mISDN/hfcpci.c:651 main_rec_hfcpci() warn: bit mask 'MAX_B_FRAMES' used for math '31 + 1'
drivers/isdn/hardware/mISDN/hfcpci.c:699 hfcpci_fill_dfifo() warn: bit mask 'MAX_D_FRAMES' used for math '15 + 1'
drivers/isdn/hardware/mISDN/hfcpci.c:725 hfcpci_fill_dfifo() warn: bit mask 'D_FREG_MASK' used for math '15 + 1'
drivers/isdn/hardware/mISDN/hfcpci.c:867 hfcpci_fill_fifo() warn: bit mask 'MAX_B_FRAMES' used for math '31 + 1'
drivers/firewire/ohci.c:1504 handle_local_rom() warn: bit mask 'CSR_CONFIG_ROM' used for math 'csr - 1024'
drivers/firewire/ohci.c:1580 handle_local_request() warn: bit mask 'CSR_REGISTER_BASE' used for math 'offset - 281474708275200'
drivers/firewire/sbp2.c:1040 sbp2_scan_unit_dir() warn: bit mask 'CSR_REGISTER_BASE' used for math '281474708275200 + 4 * value'
drivers/firewire/sbp2.c:1171 sbp2_probe() warn: bit mask 'CSR_CONFIG_ROM' used for math '(unit->directory - device->config_rom) * 4 + 1024'
drivers/block/drbd/drbd_receiver.c:3960 receive_state() warn: bit mask 'CS_VERBOSE' used for math '2 + ()'
drivers/block/rbd.c:1587 rbd_rq_fn() warn: bit mask 'SECTOR_SIZE' used for math 'blk_rq_pos(rq) * (1 << 9)'
drivers/block/rbd.c:1815 rbd_update_mapping_size() warn: bit mask 'SECTOR_SIZE' used for math 'rbd_dev->header.image_size / (1 << 9)'
drivers/block/rbd.c:1908 rbd_init_disk() warn: bit mask 'SECTOR_SIZE' used for math 'segment_size / (1 << 9)'
drivers/block/rbd.c:1920 rbd_init_disk() warn: bit mask 'SECTOR_SIZE' used for math 'rbd_dev->mapping.size / (1 << 9)'
drivers/block/rbd.c:1948 rbd_size_show() warn: bit mask 'SECTOR_SIZE' used for math 'size * (1 << 9)'
drivers/scsi/isci/host.c:2256 sci_controller_dma_alloc() warn: bit mask 'SCU_MAX_COMPLETION_QUEUE_ENTRIES' used for math '((384) + (1 << (7)) + (128) + (256) + (128)) * 4'
drivers/scsi/pm8001/pm8001_init.c:239 pm8001_alloc() warn: bit mask 'PM8001_MPI_QUEUE' used for math '1024 * 64'
drivers/scsi/pm8001/pm8001_init.c:245 pm8001_alloc() warn: bit mask 'PM8001_MPI_QUEUE' used for math '1024 * 64'
drivers/scsi/advansys.c:12161 advansys_board_found() warn: bit mask 'ASC_MAX_TID' used for math '7 + 1'
drivers/scsi/advansys.c:12172 advansys_board_found() warn: bit mask 'ADV_MAX_TID' used for math '15 + 1'
drivers/scsi/qla4xxx/ql4_nx.c:567 qla4_82xx_pci_get_crb_addr_2M() warn: bit mask 'QLA82XX_PCI_CRBSPACE' used for math ''
drivers/scsi/qla4xxx/ql4_nx.c:1100 qla4_82xx_pinit_from_rom() warn: bit mask 'QLA82XX_PCI_CRBSPACE' used for math 'qla4_82xx_decode_crb_addr(buf + i->addr) + 100663296'
drivers/scsi/qla2xxx/qla_nx.c:436 qla82xx_pci_get_crb_addr_2M() warn: bit mask 'QLA82XX_PCI_CRBSPACE' used for math ''
drivers/scsi/qla2xxx/qla_nx.c:1231 qla82xx_pinit_from_rom() warn: bit mask 'QLA82XX_PCI_CRBSPACE' used for math 'qla82xx_decode_crb_addr(buf + i->addr) + 100663296'
drivers/char/pcmcia/synclink_cs.c:2469 dtr_rts() warn: bit mask 'SerialSignal_DTR' used for math '~32 + 128'
drivers/target/sbp/sbp_target.c:2006 sbp_update_unit_directory() warn: bit mask 'CSR_REGISTER_BASE' used for math 'tport->mgt_agt->handler.offset - 281474708275200'
drivers/tty/serial/jsm/jsm_tty.c:772 jsm_check_queue_flow_control() warn: bit mask 'RQUEUEMASK' used for math '8191 + 1'
drivers/tty/serial/jsm/jsm_neo.c:312 neo_copy_data_from_uart_to_queue() warn: bit mask 'RQUEUEMASK' used for math '8191 + 1'
drivers/tty/n_gsm.c:2682 gsm_mux_rx_netchar() warn: bit mask 'NET_IP_ALIGN' used for math 'size + 0'
drivers/atm/fore200e.c:1611 fore200e_send() warn: bit mask 'ATM_CELL_PAYLOAD' used for math '((skb_len / 48) + 1) * 48'
drivers/atm/fore200e.c:1611 fore200e_send() warn: bit mask 'ATM_CELL_PAYLOAD' used for math 'skb_len / 48'
drivers/atm/zatm.c:447 poll_rx() warn: bit mask 'ATM_CELL_PAYLOAD' used for math 'cells * 48'
drivers/atm/zatm.c:448 poll_rx() warn: bit mask 'ATM_CELL_PAYLOAD' used for math '(cells - 1) * 48'
drivers/atm/zatm.c:502 open_rx_first() warn: bit mask 'ATM_CELL_PAYLOAD' used for math 'cells * 48'
drivers/atm/idt77252.c:1103 dequeue_rx() warn: bit mask 'ATM_CELL_PAYLOAD' used for math ''
drivers/atm/idt77252.c:1115 dequeue_rx() warn: bit mask 'ATM_CELL_PAYLOAD' used for math '(stat & 511) * 48'
drivers/atm/eni.c:1077 do_tx() warn: bit mask 'ATM_CELL_PAYLOAD' used for math 'skb->len + 4 * (8 / 4) + 48'
drivers/atm/eni.c:1151 do_tx() warn: bit mask 'ATM_CELL_PAYLOAD' used for math '48 / 4'
drivers/atm/horizon.c:1666 hrz_send() warn: bit mask 'ATM_CELL_PAYLOAD' used for math '(skb->len + (8 - 1)) / 48'
drivers/atm/nicstar.c:2072 dequeue_rx() warn: bit mask 'ATM_CELL_PAYLOAD' used for math ''
drivers/atm/he.c:451 he_init_rx_lbfp0() warn: bit mask 'ATM_CELL_PAYLOAD' used for math 'he_dev->cells_per_lbuf * 48'
drivers/atm/he.c:481 he_init_rx_lbfp1() warn: bit mask 'ATM_CELL_PAYLOAD' used for math 'he_dev->cells_per_lbuf * 48'
drivers/atm/he.c:511 he_init_tx_lbfp() warn: bit mask 'ATM_CELL_PAYLOAD' used for math 'he_dev->cells_per_lbuf * 48'
drivers/atm/he.c:2559 he_send() warn: bit mask 'ATM_CELL_PAYLOAD' used for math '52 - 48'
lib/bch.c:260 modulo() warn: bit mask 'n' used for math ''
lib/bch.c:272 mod_s() warn: bit mask 'n' used for math 'v - n'
lib/bch.c:401 compute_error_locator_polynomial() warn: bit mask 'n' used for math 'a_log(d, bch) + n'

[Cocci] coccinelle and bitmask arithmetic (was: Re: [patch] TTY: synclink, small cleanup in dtr_rts())

[Julia Lawall]

How about the following (from today's linux-next).  They appear to be
trying to do the same calculation, once with + and once with |.

arch/arm/common/it8152.c

int dma_set_coherent_mask(struct device *dev, u64 mask)
{
        if (mask >= PHYS_OFFSET + SZ_64M - 1)
                return 0;

        return -EIO;
}

static int it8152_pci_platform_notify(struct device *dev)
{
        if (dev->bus == &pci_bus_type) {
                if (dev->dma_mask)
                        *dev->dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
                dev->coherent_dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
                dmabounce_register_dev(dev, 2048, 4096, it8152_needs_bounce);
        }
        return 0;
}

julia

[Cocci] coccinelle and bitmask arithmetic (was: Re: [patch] TTY: synclink, small cleanup in dtr_rts())

[Joe Perches]

On Tue, 2013-01-29 at 18:49 +0100, Julia Lawall wrote:
> How about the following (from today's linux-next).  They appear to be
> trying to do the same calculation, once with + and once with |.

(cc'ing the original developer and Russell King)

Likely the it8152_pci_platform_notify uses should use +

> arch/arm/common/it8152.c
> 
> int dma_set_coherent_mask(struct device *dev, u64 mask)
> {
>         if (mask >= PHYS_OFFSET + SZ_64M - 1)
>                 return 0;
> 
>         return -EIO;
> }
> 
> static int it8152_pci_platform_notify(struct device *dev)
> {
>         if (dev->bus == &pci_bus_type) {
>                 if (dev->dma_mask)
>                         *dev->dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
>                 dev->coherent_dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
>                 dmabounce_register_dev(dev, 2048, 4096, it8152_needs_bounce);
>         }
>         return 0;
> }

[Cocci] coccinelle and bitmask arithmetic

[walter harms]

Am 29.01.2013 19:03, schrieb Joe Perches:
> On Tue, 2013-01-29 at 18:49 +0100, Julia Lawall wrote:
>> How about the following (from today's linux-next).  They appear to be
>> trying to do the same calculation, once with + and once with |.
> 
> (cc'ing the original developer and Russell King)
> 
> Likely the it8152_pci_platform_notify uses should use +
> 
>> arch/arm/common/it8152.c
>>
>> int dma_set_coherent_mask(struct device *dev, u64 mask)
>> {
>>         if (mask >= PHYS_OFFSET + SZ_64M - 1)
>>                 return 0;
>>
>>         return -EIO;
>> }
>>

Great hit Joe :)

Sometimes i am really surprised what code can be found
in the kernal and it is still working.
Having no clue of the code i suspect somebody tries to
check is mask outside the range it should read
PHYS_OFFSET |( SZ_64M - 1)
maybe someone should tell them that
1+1=10 while 1|1=1
It does not seem to matter here (or ... ?)

really perplexed,

wh


>> static int it8152_pci_platform_notify(struct device *dev)
>> {
>>         if (dev->bus == &pci_bus_type) {
>>                 if (dev->dma_mask)
>>                         *dev->dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
>>                 dev->coherent_dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
>>                 dmabounce_register_dev(dev, 2048, 4096, it8152_needs_bounce);
>>         }
>>         return 0;
>> }
> 
> 
> --
> To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> 

[Cocci] coccinelle and bitmask arithmetic

[Joe Perches]

On Wed, 2013-01-30 at 09:21 +0100, walter harms wrote:
> Am 29.01.2013 19:03, schrieb Joe Perches:
> > On Tue, 2013-01-29 at 18:49 +0100, Julia Lawall wrote:
> >> How about the following (from today's linux-next).  They appear to be
> >> trying to do the same calculation, once with + and once with |.
> > 
> > (cc'ing the original developer and Russell King)
> > 
> > Likely the it8152_pci_platform_notify uses should use +
> > 
> >> arch/arm/common/it8152.c
> >>
> >> int dma_set_coherent_mask(struct device *dev, u64 mask)
> >> {
> >>         if (mask >= PHYS_OFFSET + SZ_64M - 1)
> >>                 return 0;
> >>
> >>         return -EIO;
> >> }
> >>
> 
> Great hit Joe :)

Julia and the others in the coccinelle group are the ones
with the whizzy program.

[Cocci] coccinelle and bitmask arithmetic

[Russell King - ARM Linux]

On Wed, Jan 30, 2013 at 09:21:28AM +0100, walter harms wrote:
> Great hit Joe :)
> 
> Sometimes i am really surprised what code can be found
> in the kernal and it is still working.
> Having no clue of the code i suspect somebody tries to
> check is mask outside the range it should read
> PHYS_OFFSET |( SZ_64M - 1)
> maybe someone should tell them that
> 1+1=10 while 1|1=1
> It does not seem to matter here (or ... ?)

This PCI host is only used on one platform (ARMCORE).

For this, PHYS_OFFSET will be a value with only the top few bits of a
32-bit word set (such as 0xc0000000) - it's certainly not going to have
any bits set below bit 26 on the platform this driver gets used on.
"SZ_64M - 1" is the size of the window that RAM appears.

So, _either_ logical OR or addition works.

If we _did_ end up with a PHYS_OFFSET with bits less than bit 26 set
here, we'd have bigger problems - because the base of RAM in PCI space
will not correspond with PHYS_OFFSET and all the DMA mapping stuff breaks.

[Cocci] coccinelle and bitmask arithmetic

[Julia Lawall]

On Wed, 30 Jan 2013, Russell King - ARM Linux wrote:

> On Wed, Jan 30, 2013 at 09:21:28AM +0100, walter harms wrote:
> > Great hit Joe :)
> >
> > Sometimes i am really surprised what code can be found
> > in the kernal and it is still working.
> > Having no clue of the code i suspect somebody tries to
> > check is mask outside the range it should read
> > PHYS_OFFSET |( SZ_64M - 1)
> > maybe someone should tell them that
> > 1+1=10 while 1|1=1
> > It does not seem to matter here (or ... ?)
>
> This PCI host is only used on one platform (ARMCORE).
>
> For this, PHYS_OFFSET will be a value with only the top few bits of a
> 32-bit word set (such as 0xc0000000) - it's certainly not going to have
> any bits set below bit 26 on the platform this driver gets used on.
> "SZ_64M - 1" is the size of the window that RAM appears.
>
> So, _either_ logical OR or addition works.
>
> If we _did_ end up with a PHYS_OFFSET with bits less than bit 26 set
> here, we'd have bigger problems - because the base of RAM in PCI space
> will not correspond with PHYS_OFFSET and all the DMA mapping stuff breaks.

The "problem" is that the computation is done inconsistently within the
same file.  Sometimes with + and sometimes with |.

julia

[Cocci] coccinelle and bitmask arithmetic

[Russell King - ARM Linux]

On Wed, Jan 30, 2013 at 12:21:21PM +0100, Julia Lawall wrote:
> 
> 
> On Wed, 30 Jan 2013, Russell King - ARM Linux wrote:
> 
> > On Wed, Jan 30, 2013 at 09:21:28AM +0100, walter harms wrote:
> > > Great hit Joe :)
> > >
> > > Sometimes i am really surprised what code can be found
> > > in the kernal and it is still working.
> > > Having no clue of the code i suspect somebody tries to
> > > check is mask outside the range it should read
> > > PHYS_OFFSET |( SZ_64M - 1)
> > > maybe someone should tell them that
> > > 1+1=10 while 1|1=1
> > > It does not seem to matter here (or ... ?)
> >
> > This PCI host is only used on one platform (ARMCORE).
> >
> > For this, PHYS_OFFSET will be a value with only the top few bits of a
> > 32-bit word set (such as 0xc0000000) - it's certainly not going to have
> > any bits set below bit 26 on the platform this driver gets used on.
> > "SZ_64M - 1" is the size of the window that RAM appears.
> >
> > So, _either_ logical OR or addition works.
> >
> > If we _did_ end up with a PHYS_OFFSET with bits less than bit 26 set
> > here, we'd have bigger problems - because the base of RAM in PCI space
> > will not correspond with PHYS_OFFSET and all the DMA mapping stuff breaks.
> 
> The "problem" is that the computation is done inconsistently within the
> same file.  Sometimes with + and sometimes with |.

And I say that is not a problem; if it _does_ become a problem, there are
bigger problems that would also need solving, which given a multi-subarch
kernel become a lot lot harder.

Sure, we can just change them to all be a bitwise OR (sorry, not logical)
but that's really only half the story.

[Cocci] coccinelle and bitmask arithmetic

[Joe Perches]

On Wed, 2013-01-30 at 11:35 +0000, Russell King - ARM Linux wrote:
> On Wed, Jan 30, 2013 at 12:21:21PM +0100, Julia Lawall wrote:
> > On Wed, 30 Jan 2013, Russell King - ARM Linux wrote:
> > > So, _either_ logical OR or addition works.
> > >
> > > If we _did_ end up with a PHYS_OFFSET with bits less than bit 26 set
> > > here, we'd have bigger problems - because the base of RAM in PCI space
> > > will not correspond with PHYS_OFFSET and all the DMA mapping stuff breaks.
> > 
> > The "problem" is that the computation is done inconsistently within the
> > same file.  Sometimes with + and sometimes with |.
> 
> And I say that is not a problem; if it _does_ become a problem, there are
> bigger problems that would also need solving, which given a multi-subarch
> kernel become a lot lot harder.
> 
> Sure, we can just change them to all be a bitwise OR (sorry, not logical)
> but that's really only half the story.

As far as I can tell, there'd be a lot of +'s to
change in arch/arm and only 2 uses of | in it8152.c

$ git grep -P "\(?\s*SZ_\d+[A-Z]\s*-\s*1\s*\)?\s*\|" arch/arm
arch/arm/common/it8152.c:                       *dev->dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
arch/arm/common/it8152.c:               dev->coherent_dma_mask = (SZ_64M - 1) | PHYS_OFFSET;

$ git grep -P "\+\s*\(?\s*SZ_\d+[A-Z]\b\s*-\s*1\s*\)?" arch/arm | wc -l
460

I think consistently using + would make it simpler
for some possible future conversion.

[Cocci] coccinelle and bitmask arithmetic

[Russell King - ARM Linux]

On Wed, Jan 30, 2013 at 08:53:29AM -0800, Joe Perches wrote:
> On Wed, 2013-01-30 at 11:35 +0000, Russell King - ARM Linux wrote:
> > On Wed, Jan 30, 2013 at 12:21:21PM +0100, Julia Lawall wrote:
> > > On Wed, 30 Jan 2013, Russell King - ARM Linux wrote:
> > > > So, _either_ logical OR or addition works.
> > > >
> > > > If we _did_ end up with a PHYS_OFFSET with bits less than bit 26 set
> > > > here, we'd have bigger problems - because the base of RAM in PCI space
> > > > will not correspond with PHYS_OFFSET and all the DMA mapping stuff breaks.
> > > 
> > > The "problem" is that the computation is done inconsistently within the
> > > same file.  Sometimes with + and sometimes with |.
> > 
> > And I say that is not a problem; if it _does_ become a problem, there are
> > bigger problems that would also need solving, which given a multi-subarch
> > kernel become a lot lot harder.
> > 
> > Sure, we can just change them to all be a bitwise OR (sorry, not logical)
> > but that's really only half the story.
> 
> As far as I can tell, there'd be a lot of +'s to
> change in arch/arm and only 2 uses of | in it8152.c
> 
> $ git grep -P "\(?\s*SZ_\d+[A-Z]\s*-\s*1\s*\)?\s*\|" arch/arm
> arch/arm/common/it8152.c:                       *dev->dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
> arch/arm/common/it8152.c:               dev->coherent_dma_mask = (SZ_64M - 1) | PHYS_OFFSET;
> 
> $ git grep -P "\+\s*\(?\s*SZ_\d+[A-Z]\b\s*-\s*1\s*\)?" arch/arm | wc -l
> 460
> 
> I think consistently using + would make it simpler
> for some possible future conversion.

Respectfully, I really don't care about this at the present time.  There's
bigger fish (and kernel developers) that need frying - such as fixing the
ARM kernel so it actually boots on the platforms that it used to before
all this DT crap and DMA crap came along and sodded things up.

The issue you refer to above is petty in comparison; the above works
fine, which is more than can be said about the platform I've just tried to
boot.  Sorry.

[Cocci] coccinelle and bitmask arithmetic (was: Re: [patch] TTY: synclink, small cleanup in dtr_rts())

[Julia Lawall]

The following rule looks promising:

@r@
constant c;
identifier i;
expression e;
@@

(
e | c at i
|
e & c at i
|
e |= c at i
|
e &= c at i
)

@@
constant r.c,c1;
identifier i1;
expression e;
@@

*c1 at i1 + c

That is, the sum of two constants where at least one of them has been used
with & or |.

julia