kernel/linux.git/drivers/char, branch linux-2.6.18.y

read_zero_pagealigned() locking fix

2007-02-23T23:49:52+00:00

Ramiro Voicu hits the BUG_ON(!pte_none(*pte)) in zeromap_pte_range: kernel bugzilla 7645. Right: read_zero_pagealigned uses down_read of mmap_sem, but another thread's racing read of /dev/zero, or a normal fault, can easily set that pte again, in between zap_page_range and zeromap_page_range getting there. It's been wrong ever since 2.4.3. The simple fix is to use down_write instead, but that would serialize reads of /dev/zero more than at present: perhaps some app would be badly affected. So instead let zeromap_page_range return the error instead of BUG_ON, and read_zero_pagealigned break to the slower clear_user loop in that case - there's no need to optimize for it. Use -EEXIST for when a pte is found: BUG_ON in mmap_zero (the other user of zeromap_page_range), though it really isn't interesting there. And since mmap_zero wants -EAGAIN for out-of-memory, the zeromaps better return that than -ENOMEM. Signed-off-by: Hugh Dickins Cc: Ramiro Voicu: Signed-off-by: Andrew Morton Signed-off-by: Chris Wright Signed-off-by: Greg Kroah-Hartman

[PATCH] AGP: Allocate AGP pages with GFP_DMA32 by default

2006-12-02T00:12:37+00:00

Not all graphic page remappers support physical addresses over the 4GB mark for remapping, so while some do (the AMD64 GART always did, and I just fixed the i965 to do so properly), we're safest off just forcing GFP_DMA32 allocations to make sure graphics pages get allocated in the low 32-bit address space by default. AGP sub-drivers that really care, and can do better, could just choose to implement their own allocator (or we could add another "64-bit safe" default allocator for their use), but quite frankly, you're not likely to care in practice. So for now, this trivial change means that we won't be allocating pages that we can't map correctly by mistake on x86-64. [ On traditional 32-bit x86, this could never happen, because GFP_KERNEL would never allocate any highmem memory anyway ] Acked-by: Andi Kleen Acked-by: Dave Jones Cc: Eric Anholt Cc: Keith Packard Signed-off-by: Linus Torvalds Signed-off-by: Chris Wright

[PATCH] Char: isicom, fix close bug

2006-11-19T03:28:05+00:00

port is dereferenced even if it is NULL. Dereference it _after_ the check if (!port)... Thanks Eric for reporting this. This fixes http://bugzilla.kernel.org/show_bug.cgi?id=7527 Signed-off-by: Jiri Slaby Signed-off-by: Linus Torvalds Signed-off-by: Chris Wright

[PATCH] ipmi_si_intf.c sets bad class_mask with PCI_DEVICE_CLASS

2006-11-19T03:28:01+00:00

Taken from http://bugzilla.kernel.org/show_bug.cgi?id=7439 It looks like device registration in drivers/char/ipmi/ipmi_si_intf.c was cleaned up and a small error was made when setting the class_mask. The fix is simple as the correct mask value is defined in the code but is not used. Acked-by: Corey Minyard Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Chris Wright

[PATCH] fix Intel RNG detection

2006-11-04T01:33:49+00:00

Previously, since determination whether there was an Intel random number generator was based on a single bit, on systems with a matching bridge device but without a firmware hub, there was a 50% chance that the code would incorrectly decide that the system had an RNG. This patch adds detection of the firmware hub to better qualify the existence of an RNG. There is one issue with the patch: I was unable to determine the LPC equivalent for the PCI bridge 8086:2430 (since the old code didn't care about which of the many devices provided by the ICH/ESB it was chose to use the PCI bridge device, but the FWH settings live in the LPC device, so the device list needed to be changed). Signed-off-by: Jan Beulich Signed-off-by: Michael Buesch Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman Signed-off-by: Chris Wright

[PATCH] Watchdog: sc1200wdt - fix missing pnp_unregister_driver()

2006-11-04T01:33:48+00:00

[WATCHDOG] sc1200wdt.c pnp unregister fix. If no devices found or invalid parameter is specified, scl200wdt_pnp_driver is left unregistered. It breaks global list of pnp drivers. Signed-off-by: Akinobu Mita Signed-off-by: Wim Van Sebroeck Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman Signed-off-by: Chris Wright

rtc: lockdep fix/workaround

2006-10-13T20:23:25+00:00

BUG: warning at kernel/lockdep.c:1816/trace_hardirqs_on() (Not tainted) [] show_trace_log_lvl+0x58/0x171 [] show_trace+0xd/0x10 [] dump_stack+0x19/0x1b [] trace_hardirqs_on+0xa2/0x11e [] _spin_unlock_irq+0x22/0x26 [] rtc_get_rtc_time+0x32/0x176 [] hpet_rtc_interrupt+0x92/0x14d [] handle_IRQ_event+0x20/0x4d [] __do_IRQ+0x94/0xef [] do_IRQ+0x9e/0xbd [] common_interrupt+0x25/0x2c DWARF2 unwinder stuck at common_interrupt+0x25/0x2c Signed-off-by: Peter Zijlstra Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

[PATCH] IPMI: fix handling of OEM flags

2006-09-16T19:54:31+00:00

If one of the OEM flags becomes set in the flags from the hardware, the driver could hang if no OEM handler was set. Fix the code to handle this. This was tested by setting the flags by hand after they were fetched. Signed-off-by: Corey Minyard Ackde-by: Matt Domsch Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] hvc_console suspend fix

2006-09-16T19:54:31+00:00

Fix http://bugzilla.kernel.org/show_bug.cgi?id=7152 Cc: Michael Tautschnig Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] IPMI: Fix oops on ipmi_msghandler removal for non ipmi systems

2006-09-16T19:54:30+00:00

When the ipmi_si module is loaded on a system without any ipmi device, it fails with nodev. It would be fine if all resources were freed. A call to device_unregister() is missing, resulting to a oops when you remove the ipmi_msghandler. Signed-off-by: Arnaud Patard Acked-by: Corey Minyard Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds