user/sven/linux.git/arch/tile/kernel/stack.c, branch v4.9.254

tile: include the syscall number in the backtrace

2016-01-18T19:49:16Z

This information is easily available in the backtrace data and can be helpful when trying to figure out the backtrace, particularly if we're early in kernel entry or late in kernel exit. Signed-off-by: Chris Metcalf

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2015-07-05T02:36:06Z

Pull more vfs updates from Al Viro: "Assorted VFS fixes and related cleanups (IMO the most interesting in that part are f_path-related things and Eric's descriptor-related stuff). UFS regression fixes (it got broken last cycle). 9P fixes. fs-cache series, DAX patches, Jan's file_remove_suid() work" [ I'd say this is much more than "fixes and related cleanups". The file_table locking rule change by Eric Dumazet is a rather big and fundamental update even if the patch isn't huge. - Linus ] * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits) 9p: cope with bogus responses from server in p9_client_{read,write} p9_client_write(): avoid double p9_free_req() 9p: forgetting to cancel request on interrupted zero-copy RPC dax: bdev_direct_access() may sleep block: Add support for DAX reads/writes to block devices dax: Use copy_from_iter_nocache dax: Add block size note to documentation fs/file.c: __fget() and dup2() atomicity rules fs/file.c: don't acquire files->file_lock in fd_install() fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation vfs: avoid creation of inode number 0 in get_next_ino namei: make set_root_rcu() return void make simple_positive() public ufs: use dir_pages instead of ufs_dir_pages() pagemap.h: move dir_pages() over there remove the pointless include of lglock.h fs: cleanup slight list_entry abuse xfs: Correctly lock inode when removing suid and file capabilities fs: Call security_ops->inode_killpriv on truncate fs: Provide function telling whether file_remove_privs() will do anything ...

vfs: add file_path() helper

2015-06-23T22:00:05Z

Turn d_path(&file->f_path, ...); into file_path(file, ...); Signed-off-by: Miklos Szeredi Signed-off-by: Al Viro

tile: improve stack backtrace

2015-05-11T15:22:40Z

This commit fixes a number of issues with the tile backtrace code. - Don't try to identify userspace shared object or executable paths if we are doing a backtrace from an interrupt; it's not legal, and also unlikely to be interesting. Likewise, don't try to do it for other address spaces, since d_path() assumes it is being called in "current" context. - Move "in_backtrace" from thread_struct to thread_info. This way we can access it even if our stack thread_info has been clobbered, which makes backtracing more robust. - Avoid using "current" directly when testing for is_sigreturn(). Since "current" may be corrupt, we're better off using kbt->task explicitly to look up the vdso_base for the current task. Conveniently, this simplifies the internal APIs (we only need one is_sigreturn() function now). - Avoid bogus "Odd fault" warning when pc/sp/ex1 are all zero, as is true for kernel threads above the last frame. - Hook into Tejun Heo's dump_stack() framework in lib/dump_stack.c. - Write last entry in save_stack_trace() as ULONG_MAX, not zero, since ftrace (at least) relies on finding that marker. - Implement save_stack_trace_regs() and save_strack_trace_user(), and set CONFIG_USER_STACKTRACE_SUPPORT. Signed-off-by: Chris Metcalf

arch: tile: fix null pointer dereference on pt_regs pointer

2015-04-17T16:58:41Z

Cppcheck reports the following issue: [arch/tile/kernel/stack.c:116]: (error) Possible null pointer dereference: p In this case, on reporting on an odd fault, p is set to NULL and immediately afterwords p is dereferenced iff !kbt->profile is false. Rather than doing this check just return NULL rather than falling through to the potential null pointer dereference (since the original intentional outcome would be to return NULL anyhow) for this odd fault case. Signed-off-by: Colin Ian King Signed-off-by: Chris Metcalf [tweaked lightly]

tile: Use the more common pr_warn instead of pr_warning

2014-11-11T20:51:42Z

And other message logging neatening. Other miscellanea: o coalesce formats o realign arguments o standardize a couple of macros o use __func__ instead of embedding the function name Signed-off-by: Joe Perches Signed-off-by: Chris Metcalf

arch: tile: re-use kbasename() helper

2013-09-30T14:34:46Z

kbasename() returns the filename part of a pathname. Signed-off-by: Andy Shevchenko

tile: don't assume user privilege is zero

2013-09-03T18:45:52Z

Technically, user privilege is anything less than kernel privilege. We modify the existing user_mode() macro to have this semantic (and use it in a couple of places it wasn't being used before), and add an IS_KERNEL_EX1() macro to the assembly code as well. Signed-off-by: Chris Metcalf

tilegx: change how we find the kernel stack

2013-08-30T15:56:58Z

Previously, we used a special-purpose register (SPR_SYSTEM_SAVE_K_0) to hold the CPU number and the top of the current kernel stack by using the low bits to hold the CPU number, and using the high bits to hold the address of the page just above where we'd want the kernel stack to be. That way we could initialize a new SP when first entering the kernel by just masking the SPR value and subtracting a couple of words. However, it's actually more useful to be able to place an arbitrary kernel-top value in the SPR. This allows us to create a new stack context (e.g. for virtualization) with an arbitrary top-of-stack VA. To make this work, we now store the CPU number in the high bits, above the highest legal VA bit (42 bits in the current tilegx microarchitecture). The full 42 bits are thus available to store the top of stack value. Getting the current cpu (a relatively common operation) is still fast; it's now a shift rather than a mask. We make this change only for tilegx, since tilepro has too few SPR bits to do this, and we don't need this support on tilepro anyway. Signed-off-by: Chris Metcalf

tile: implement gettimeofday() via vDSO

2013-08-13T20:26:21Z

This change creates the framework for vDSO calls, makes the existing rt_sigreturn() mechanism use it, and adds a fast gettimeofday(). Now that we need to expose the vDSO address to userspace, we add AT_SYSINFO_EHDR to the set of aux entries provided to userspace. (You can disable any extra vDSO support by booting with vdso=0, but the rt_sigreturn vDSO page will still be provided.) Note that glibc has supported the tile vDSO since release 2.17. Signed-off-by: Chris Metcalf