Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 26/08/07, Jan Engelhardt <[EMAIL PROTECTED]> wrote: > > On Aug 26 2007 15:28, Denys Vlasenko wrote: > >> > > >> > What exactely would using kcalloc() over kzalloc() here buy us? > >> > >> technically, nothing. > > > >The idea of calloc is that it can check for underflow in parameter. > > Actually, overflow. > > calloc(0x, 0x1000) => will return NULL > malloc(0x * 0x1000) => silent 32 bit multiplication/truncation, > will allocate less than requested. > > >calloc(-1, 1000) => easy to detect > >malloc(-1 * 1000) => malloc(-1000) => not so trivial > Ok, that makes a bit of sense. Thank you. -- Jesper Juhl <[EMAIL PROTECTED]> Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Aug 26 2007 15:28, Denys Vlasenko wrote: >> > >> > What exactely would using kcalloc() over kzalloc() here buy us? >> >> technically, nothing. > >The idea of calloc is that it can check for underflow in parameter. Actually, overflow. calloc(0x, 0x1000) => will return NULL malloc(0x * 0x1000) => silent 32 bit multiplication/truncation, will allocate less than requested. >calloc(-1, 1000) => easy to detect >malloc(-1 * 1000) => malloc(-1000) => not so trivial Jan -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Sunday 26 August 2007 01:23, Robert P. J. Day wrote: > On Sun, 26 Aug 2007, Jesper Juhl wrote: > > On 26/08/07, Robert P. J. Day <[EMAIL PROTECTED]> wrote: > > > i was thinking more along the lines of > > > > > > msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); > > > > > > which was kind of the obvious implication, no? > > > > I guess > > > > > unless there's a reason kcalloc() wouldn't work here, this is > > > pretty much what kcalloc() was designed for. > > > > When Denys brought up the zeroing thing and mentioned kzalloc() I > > did consider kcalloc() instead, but kzalloc() makes this allocation > > nicely look like the preceding ones visually and I couldn't convince > > myself that kcalloc() would give us any real benefit here. > > > > What exactely would using kcalloc() over kzalloc() here buy us? > > technically, nothing. The idea of calloc is that it can check for underflow in parameter. calloc(-1, 1000) => easy to detect malloc(-1 * 1000) => malloc(-1000) => not so trivial -- vda - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Sunday 26 August 2007 01:23, Robert P. J. Day wrote: On Sun, 26 Aug 2007, Jesper Juhl wrote: On 26/08/07, Robert P. J. Day [EMAIL PROTECTED] wrote: i was thinking more along the lines of msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); which was kind of the obvious implication, no? I guess unless there's a reason kcalloc() wouldn't work here, this is pretty much what kcalloc() was designed for. When Denys brought up the zeroing thing and mentioned kzalloc() I did consider kcalloc() instead, but kzalloc() makes this allocation nicely look like the preceding ones visually and I couldn't convince myself that kcalloc() would give us any real benefit here. What exactely would using kcalloc() over kzalloc() here buy us? technically, nothing. The idea of calloc is that it can check for underflow in parameter. calloc(-1, 1000) = easy to detect malloc(-1 * 1000) = malloc(-1000) = not so trivial -- vda - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Aug 26 2007 15:28, Denys Vlasenko wrote: What exactely would using kcalloc() over kzalloc() here buy us? technically, nothing. The idea of calloc is that it can check for underflow in parameter. Actually, overflow. calloc(0x, 0x1000) = will return NULL malloc(0x * 0x1000) = silent 32 bit multiplication/truncation, will allocate less than requested. calloc(-1, 1000) = easy to detect malloc(-1 * 1000) = malloc(-1000) = not so trivial Jan -- - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 26/08/07, Jan Engelhardt [EMAIL PROTECTED] wrote: On Aug 26 2007 15:28, Denys Vlasenko wrote: What exactely would using kcalloc() over kzalloc() here buy us? technically, nothing. The idea of calloc is that it can check for underflow in parameter. Actually, overflow. calloc(0x, 0x1000) = will return NULL malloc(0x * 0x1000) = silent 32 bit multiplication/truncation, will allocate less than requested. calloc(-1, 1000) = easy to detect malloc(-1 * 1000) = malloc(-1000) = not so trivial Ok, that makes a bit of sense. Thank you. -- Jesper Juhl [EMAIL PROTECTED] Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Aug 25, 2007, at 20:36:32, Jesper Juhl wrote: On 26/08/07, Robert P. J. Day <[EMAIL PROTECTED]> wrote: technically, nothing. but if you're not going to use kcalloc() when you're explicitly allocating an array of identical objects (that you want zero-filled, as a bonus), then what's the point of ever having defined a kcalloc() routine in the first place? I wonder a bit about that myself... I have found some other issues in that function that I want to fix, so I'll be respinning the patch as a patch series instead - and why not; I'll just go with kcalloc() and see what the maintainers have to say, it's not like I personally care much one way or the other. I think the original reasoning behind kcalloc() was that it did some extra input checking, so that if the product of the two numbers overflowed, it would fail with NULL instead of allocating insufficient space. In the kernel it doesn't matter in practice since you MUST have additional checking on the size of allocated memory anyways, not even considering the fact that >PAGE_SIZE allocations are probably going to fail with decent frequency regardless. Cheers, Kyle Moffett - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 26/08/07, Robert P. J. Day <[EMAIL PROTECTED]> wrote: > On Sun, 26 Aug 2007, Jesper Juhl wrote: > > > On 26/08/07, Robert P. J. Day <[EMAIL PROTECTED]> wrote: > > > > i was thinking more along the lines of > > > > > > msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); > > > > > > which was kind of the obvious implication, no? > > > > I guess > > > > > unless there's a reason kcalloc() wouldn't work here, this is > > > pretty much what kcalloc() was designed for. > > > > > When Denys brought up the zeroing thing and mentioned kzalloc() I > > did consider kcalloc() instead, but kzalloc() makes this allocation > > nicely look like the preceding ones visually and I couldn't convince > > myself that kcalloc() would give us any real benefit here. > > > > What exactely would using kcalloc() over kzalloc() here buy us? > > technically, nothing. but if you're not going to use kcalloc() when > you're explicitly allocating an array of identical objects (that you > want zero-filled, as a bonus), then what's the point of ever having > defined a kcalloc() routine in the first place? > I wonder a bit about that myself... I have found some other issues in that function that I want to fix, so I'll be respinning the patch as a patch series instead - and why not; I'll just go with kcalloc() and see what the maintainers have to say, it's not like I personally care much one way or the other. -- Jesper Juhl <[EMAIL PROTECTED]> Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Sun, 26 Aug 2007, Jesper Juhl wrote: > On 26/08/07, Robert P. J. Day <[EMAIL PROTECTED]> wrote: > > i was thinking more along the lines of > > > > msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); > > > > which was kind of the obvious implication, no? > > I guess > > > unless there's a reason kcalloc() wouldn't work here, this is > > pretty much what kcalloc() was designed for. > > > When Denys brought up the zeroing thing and mentioned kzalloc() I > did consider kcalloc() instead, but kzalloc() makes this allocation > nicely look like the preceding ones visually and I couldn't convince > myself that kcalloc() would give us any real benefit here. > > What exactely would using kcalloc() over kzalloc() here buy us? technically, nothing. but if you're not going to use kcalloc() when you're explicitly allocating an array of identical objects (that you want zero-filled, as a bonus), then what's the point of ever having defined a kcalloc() routine in the first place? rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://crashcourse.ca - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 26/08/07, Robert P. J. Day <[EMAIL PROTECTED]> wrote: > On Sun, 26 Aug 2007, Jesper Juhl wrote: > > > On 24/08/07, Robert P. J. Day <[EMAIL PROTECTED]> wrote: > > > > actually, i would think kcalloc would be more appropriate here, no? > > > > > > > Why? > > > > msp_parts[i] = kzalloc(pcnt * sizeof(struct mtd_partition), GFP_KERNEL); > > > > seems better to me than > > > > msp_parts[i] = kcalloc(1, pcnt * sizeof(struct mtd_partition), GFP_KERNEL); > > i was thinking more along the lines of > > msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); > > which was kind of the obvious implication, no? I guess > unless there's a > reason kcalloc() wouldn't work here, this is pretty much what > kcalloc() was designed for. > When Denys brought up the zeroing thing and mentioned kzalloc() I did consider kcalloc() instead, but kzalloc() makes this allocation nicely look like the preceding ones visually and I couldn't convince myself that kcalloc() would give us any real benefit here. What exactely would using kcalloc() over kzalloc() here buy us? -- Jesper Juhl <[EMAIL PROTECTED]> Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Sun, 26 Aug 2007, Jesper Juhl wrote: > On 24/08/07, Robert P. J. Day <[EMAIL PROTECTED]> wrote: > > actually, i would think kcalloc would be more appropriate here, no? > > > > Why? > > msp_parts[i] = kzalloc(pcnt * sizeof(struct mtd_partition), GFP_KERNEL); > > seems better to me than > > msp_parts[i] = kcalloc(1, pcnt * sizeof(struct mtd_partition), GFP_KERNEL); i was thinking more along the lines of msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); which was kind of the obvious implication, no? unless there's a reason kcalloc() wouldn't work here, this is pretty much what kcalloc() was designed for. rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://crashcourse.ca - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 24/08/07, Robert P. J. Day <[EMAIL PROTECTED]> wrote: > On Fri, 24 Aug 2007, Denys Vlasenko wrote: > > > On Friday 24 August 2007 00:52, Jesper Juhl wrote: > > > kmalloc() returns a void pointer. > > > No need to cast it. > > > > > - msp_flash = (struct mtd_info **)kmalloc( > > > - fcnt * sizeof(struct map_info *), GFP_KERNEL); > > > - msp_parts = (struct mtd_partition **)kmalloc( > > > - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); > > > - msp_maps = (struct map_info *)kmalloc( > > > - fcnt * sizeof(struct mtd_info), GFP_KERNEL); > > > + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); > > > + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), > > > GFP_KERNEL); > > > + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); > > > memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); > > > > This one wants kzalloc. > > > > > - msp_parts[i] = (struct mtd_partition *)kmalloc( > > > - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); > > > + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), > > > + GFP_KERNEL); > > > memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); > > > > > > /* now initialize the devices proper */ > > > > Same > > actually, i would think kcalloc would be more appropriate here, no? > Why? msp_parts[i] = kzalloc(pcnt * sizeof(struct mtd_partition), GFP_KERNEL); seems better to me than msp_parts[i] = kcalloc(1, pcnt * sizeof(struct mtd_partition), GFP_KERNEL); -- Jesper Juhl <[EMAIL PROTECTED]> Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 24/08/07, Robert P. J. Day [EMAIL PROTECTED] wrote: On Fri, 24 Aug 2007, Denys Vlasenko wrote: On Friday 24 August 2007 00:52, Jesper Juhl wrote: kmalloc() returns a void pointer. No need to cast it. - msp_flash = (struct mtd_info **)kmalloc( - fcnt * sizeof(struct map_info *), GFP_KERNEL); - msp_parts = (struct mtd_partition **)kmalloc( - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); - msp_maps = (struct map_info *)kmalloc( - fcnt * sizeof(struct mtd_info), GFP_KERNEL); + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); This one wants kzalloc. - msp_parts[i] = (struct mtd_partition *)kmalloc( - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), + GFP_KERNEL); memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); /* now initialize the devices proper */ Same actually, i would think kcalloc would be more appropriate here, no? Why? msp_parts[i] = kzalloc(pcnt * sizeof(struct mtd_partition), GFP_KERNEL); seems better to me than msp_parts[i] = kcalloc(1, pcnt * sizeof(struct mtd_partition), GFP_KERNEL); -- Jesper Juhl [EMAIL PROTECTED] Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Sun, 26 Aug 2007, Jesper Juhl wrote: On 24/08/07, Robert P. J. Day [EMAIL PROTECTED] wrote: actually, i would think kcalloc would be more appropriate here, no? Why? msp_parts[i] = kzalloc(pcnt * sizeof(struct mtd_partition), GFP_KERNEL); seems better to me than msp_parts[i] = kcalloc(1, pcnt * sizeof(struct mtd_partition), GFP_KERNEL); i was thinking more along the lines of msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); which was kind of the obvious implication, no? unless there's a reason kcalloc() wouldn't work here, this is pretty much what kcalloc() was designed for. rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://crashcourse.ca - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 26/08/07, Robert P. J. Day [EMAIL PROTECTED] wrote: On Sun, 26 Aug 2007, Jesper Juhl wrote: On 24/08/07, Robert P. J. Day [EMAIL PROTECTED] wrote: actually, i would think kcalloc would be more appropriate here, no? Why? msp_parts[i] = kzalloc(pcnt * sizeof(struct mtd_partition), GFP_KERNEL); seems better to me than msp_parts[i] = kcalloc(1, pcnt * sizeof(struct mtd_partition), GFP_KERNEL); i was thinking more along the lines of msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); which was kind of the obvious implication, no? I guess unless there's a reason kcalloc() wouldn't work here, this is pretty much what kcalloc() was designed for. When Denys brought up the zeroing thing and mentioned kzalloc() I did consider kcalloc() instead, but kzalloc() makes this allocation nicely look like the preceding ones visually and I couldn't convince myself that kcalloc() would give us any real benefit here. What exactely would using kcalloc() over kzalloc() here buy us? -- Jesper Juhl [EMAIL PROTECTED] Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Sun, 26 Aug 2007, Jesper Juhl wrote: On 26/08/07, Robert P. J. Day [EMAIL PROTECTED] wrote: i was thinking more along the lines of msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); which was kind of the obvious implication, no? I guess unless there's a reason kcalloc() wouldn't work here, this is pretty much what kcalloc() was designed for. When Denys brought up the zeroing thing and mentioned kzalloc() I did consider kcalloc() instead, but kzalloc() makes this allocation nicely look like the preceding ones visually and I couldn't convince myself that kcalloc() would give us any real benefit here. What exactely would using kcalloc() over kzalloc() here buy us? technically, nothing. but if you're not going to use kcalloc() when you're explicitly allocating an array of identical objects (that you want zero-filled, as a bonus), then what's the point of ever having defined a kcalloc() routine in the first place? rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://crashcourse.ca - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 26/08/07, Robert P. J. Day [EMAIL PROTECTED] wrote: On Sun, 26 Aug 2007, Jesper Juhl wrote: On 26/08/07, Robert P. J. Day [EMAIL PROTECTED] wrote: i was thinking more along the lines of msp_parts[i] = kcalloc(pcnt, sizeof(struct mtd_partition), GFP_KERNEL); which was kind of the obvious implication, no? I guess unless there's a reason kcalloc() wouldn't work here, this is pretty much what kcalloc() was designed for. When Denys brought up the zeroing thing and mentioned kzalloc() I did consider kcalloc() instead, but kzalloc() makes this allocation nicely look like the preceding ones visually and I couldn't convince myself that kcalloc() would give us any real benefit here. What exactely would using kcalloc() over kzalloc() here buy us? technically, nothing. but if you're not going to use kcalloc() when you're explicitly allocating an array of identical objects (that you want zero-filled, as a bonus), then what's the point of ever having defined a kcalloc() routine in the first place? I wonder a bit about that myself... I have found some other issues in that function that I want to fix, so I'll be respinning the patch as a patch series instead - and why not; I'll just go with kcalloc() and see what the maintainers have to say, it's not like I personally care much one way or the other. -- Jesper Juhl [EMAIL PROTECTED] Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Aug 25, 2007, at 20:36:32, Jesper Juhl wrote: On 26/08/07, Robert P. J. Day [EMAIL PROTECTED] wrote: technically, nothing. but if you're not going to use kcalloc() when you're explicitly allocating an array of identical objects (that you want zero-filled, as a bonus), then what's the point of ever having defined a kcalloc() routine in the first place? I wonder a bit about that myself... I have found some other issues in that function that I want to fix, so I'll be respinning the patch as a patch series instead - and why not; I'll just go with kcalloc() and see what the maintainers have to say, it's not like I personally care much one way or the other. I think the original reasoning behind kcalloc() was that it did some extra input checking, so that if the product of the two numbers overflowed, it would fail with NULL instead of allocating insufficient space. In the kernel it doesn't matter in practice since you MUST have additional checking on the size of allocated memory anyways, not even considering the fact that PAGE_SIZE allocations are probably going to fail with decent frequency regardless. Cheers, Kyle Moffett - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Fri, 24 Aug 2007, Denys Vlasenko wrote: > On Friday 24 August 2007 00:52, Jesper Juhl wrote: > > kmalloc() returns a void pointer. > > No need to cast it. > > > - msp_flash = (struct mtd_info **)kmalloc( > > - fcnt * sizeof(struct map_info *), GFP_KERNEL); > > - msp_parts = (struct mtd_partition **)kmalloc( > > - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); > > - msp_maps = (struct map_info *)kmalloc( > > - fcnt * sizeof(struct mtd_info), GFP_KERNEL); > > + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); > > + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); > > + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); > > memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); > > This one wants kzalloc. > > > - msp_parts[i] = (struct mtd_partition *)kmalloc( > > - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); > > + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), > > + GFP_KERNEL); > > memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); > > > > /* now initialize the devices proper */ > > Same actually, i would think kcalloc would be more appropriate here, no? rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://crashcourse.ca - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 24/08/07, Denys Vlasenko <[EMAIL PROTECTED]> wrote: > On Friday 24 August 2007 00:52, Jesper Juhl wrote: > > kmalloc() returns a void pointer. > > No need to cast it. > > > - msp_flash = (struct mtd_info **)kmalloc( > > - fcnt * sizeof(struct map_info *), GFP_KERNEL); > > - msp_parts = (struct mtd_partition **)kmalloc( > > - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); > > - msp_maps = (struct map_info *)kmalloc( > > - fcnt * sizeof(struct mtd_info), GFP_KERNEL); > > + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); > > + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), > > GFP_KERNEL); > > + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); > > memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); > > This one wants kzalloc. > > > - msp_parts[i] = (struct mtd_partition *)kmalloc( > > - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); > > + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), > > + GFP_KERNEL); > > memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); > > > > /* now initialize the devices proper */ > > Same Ok, thank you for that feedback. I'll respin the patch with that change when I resubmit all the ones that don't get picked up (probably next week). -- Jesper Juhl <[EMAIL PROTECTED]> Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Friday 24 August 2007 00:52, Jesper Juhl wrote: > kmalloc() returns a void pointer. > No need to cast it. > - msp_flash = (struct mtd_info **)kmalloc( > - fcnt * sizeof(struct map_info *), GFP_KERNEL); > - msp_parts = (struct mtd_partition **)kmalloc( > - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); > - msp_maps = (struct map_info *)kmalloc( > - fcnt * sizeof(struct mtd_info), GFP_KERNEL); > + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); > + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); > + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); > memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); This one wants kzalloc. > - msp_parts[i] = (struct mtd_partition *)kmalloc( > - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); > + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), > + GFP_KERNEL); > memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); > > /* now initialize the devices proper */ Same -- vda - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Friday 24 August 2007 00:52, Jesper Juhl wrote: kmalloc() returns a void pointer. No need to cast it. - msp_flash = (struct mtd_info **)kmalloc( - fcnt * sizeof(struct map_info *), GFP_KERNEL); - msp_parts = (struct mtd_partition **)kmalloc( - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); - msp_maps = (struct map_info *)kmalloc( - fcnt * sizeof(struct mtd_info), GFP_KERNEL); + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); This one wants kzalloc. - msp_parts[i] = (struct mtd_partition *)kmalloc( - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), + GFP_KERNEL); memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); /* now initialize the devices proper */ Same -- vda - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On 24/08/07, Denys Vlasenko [EMAIL PROTECTED] wrote: On Friday 24 August 2007 00:52, Jesper Juhl wrote: kmalloc() returns a void pointer. No need to cast it. - msp_flash = (struct mtd_info **)kmalloc( - fcnt * sizeof(struct map_info *), GFP_KERNEL); - msp_parts = (struct mtd_partition **)kmalloc( - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); - msp_maps = (struct map_info *)kmalloc( - fcnt * sizeof(struct mtd_info), GFP_KERNEL); + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); This one wants kzalloc. - msp_parts[i] = (struct mtd_partition *)kmalloc( - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), + GFP_KERNEL); memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); /* now initialize the devices proper */ Same Ok, thank you for that feedback. I'll respin the patch with that change when I resubmit all the ones that don't get picked up (probably next week). -- Jesper Juhl [EMAIL PROTECTED] Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
On Fri, 24 Aug 2007, Denys Vlasenko wrote: On Friday 24 August 2007 00:52, Jesper Juhl wrote: kmalloc() returns a void pointer. No need to cast it. - msp_flash = (struct mtd_info **)kmalloc( - fcnt * sizeof(struct map_info *), GFP_KERNEL); - msp_parts = (struct mtd_partition **)kmalloc( - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); - msp_maps = (struct map_info *)kmalloc( - fcnt * sizeof(struct mtd_info), GFP_KERNEL); + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); This one wants kzalloc. - msp_parts[i] = (struct mtd_partition *)kmalloc( - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), + GFP_KERNEL); memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); /* now initialize the devices proper */ Same actually, i would think kcalloc would be more appropriate here, no? rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://crashcourse.ca - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
kmalloc() returns a void pointer. No need to cast it. Signed-off-by: Jesper Juhl <[EMAIL PROTECTED]> --- drivers/mtd/maps/pmcmsp-flash.c | 13 + 1 files changed, 5 insertions(+), 8 deletions(-) diff --git a/drivers/mtd/maps/pmcmsp-flash.c b/drivers/mtd/maps/pmcmsp-flash.c index 7e0377e..dfdb120 100644 --- a/drivers/mtd/maps/pmcmsp-flash.c +++ b/drivers/mtd/maps/pmcmsp-flash.c @@ -73,12 +73,9 @@ int __init init_msp_flash(void) return -ENXIO; printk(KERN_NOTICE "Found %d PMC flash devices\n", fcnt); - msp_flash = (struct mtd_info **)kmalloc( - fcnt * sizeof(struct map_info *), GFP_KERNEL); - msp_parts = (struct mtd_partition **)kmalloc( - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); - msp_maps = (struct map_info *)kmalloc( - fcnt * sizeof(struct mtd_info), GFP_KERNEL); + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); /* loop over the flash devices, initializing each */ @@ -95,8 +92,8 @@ int __init init_msp_flash(void) continue; } - msp_parts[i] = (struct mtd_partition *)kmalloc( - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), + GFP_KERNEL); memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); /* now initialize the devices proper */ -- 1.5.2.2 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 09/30] mtd: Don't cast kmalloc() return value in drivers/mtd/maps/pmcmsp-flash.c
kmalloc() returns a void pointer. No need to cast it. Signed-off-by: Jesper Juhl [EMAIL PROTECTED] --- drivers/mtd/maps/pmcmsp-flash.c | 13 + 1 files changed, 5 insertions(+), 8 deletions(-) diff --git a/drivers/mtd/maps/pmcmsp-flash.c b/drivers/mtd/maps/pmcmsp-flash.c index 7e0377e..dfdb120 100644 --- a/drivers/mtd/maps/pmcmsp-flash.c +++ b/drivers/mtd/maps/pmcmsp-flash.c @@ -73,12 +73,9 @@ int __init init_msp_flash(void) return -ENXIO; printk(KERN_NOTICE Found %d PMC flash devices\n, fcnt); - msp_flash = (struct mtd_info **)kmalloc( - fcnt * sizeof(struct map_info *), GFP_KERNEL); - msp_parts = (struct mtd_partition **)kmalloc( - fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); - msp_maps = (struct map_info *)kmalloc( - fcnt * sizeof(struct mtd_info), GFP_KERNEL); + msp_flash = kmalloc(fcnt * sizeof(struct map_info *), GFP_KERNEL); + msp_parts = kmalloc(fcnt * sizeof(struct mtd_partition *), GFP_KERNEL); + msp_maps = kmalloc(fcnt * sizeof(struct mtd_info), GFP_KERNEL); memset(msp_maps, 0, fcnt * sizeof(struct mtd_info)); /* loop over the flash devices, initializing each */ @@ -95,8 +92,8 @@ int __init init_msp_flash(void) continue; } - msp_parts[i] = (struct mtd_partition *)kmalloc( - pcnt * sizeof(struct mtd_partition), GFP_KERNEL); + msp_parts[i] = kmalloc(pcnt * sizeof(struct mtd_partition), + GFP_KERNEL); memset(msp_parts[i], 0, pcnt * sizeof(struct mtd_partition)); /* now initialize the devices proper */ -- 1.5.2.2 - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
